JSSStandards JSS 52300 1992

RAKSHA MANTRALAYA MINISTRY OF DEFENCE

JOINT SERVICES SPECIFICATION

ON

GENERAL REQUIREMENTS FOR PRINTED WIRING BOARDS

JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003

MANAKIKARAN NIDESHALAYA RAKSHA UTPADAN TATHA POORTI VIBHAG

RAKSHA MANTRALAYA, 'H' BLOCK, NIRMAN BHAWAN PO NEW DELHI - 110 011

DIRECTORATE OF STANDARDISATION DEPARTMENT OF PRODUCTION & SUPPLIES

MINISTRY OF DEFENCE, 'H'- BLOCK, NIRMAN BHAWAN PO NEW DELHI - 110 011


RAKSHA MANTRALAYA MINISTRY OF DEFENCE

JOINT SERVICES SPECIFICATION

ON

GENERAL REQUIREMENTS FOR PRINTED WIRING BOARDS

MANAKIKARAN NIDESHALAYA RAKSHA UTPADAN TATHA POORTI VIBHAG

RAKSHA MANTRALAYA, 'H' BLOCK, NIRMAN BHAWAN PO NEW DELHI - 110 011

DIRECTORATE OF STANDARDISATION DEPARTMENT OF PRODUCTION & SUPPLIES

MINISTRY OF DEFENCE, 'H'- BLOCK, NIRMAN BHAWAN PO NEW DELHI - 110 011

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RECORD OF AMENDMENTS

Amendment Amended by

No. Date

Amendment pertains to: Sl.No./ Para No./ Column No.

Authority Name & Appointment (IN BLOCK LETTERS)

Signature &

Date

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CONTENTS S.No. Page

No.

0. FOREWORD 1

1. SCOPE 2

2. RELATED SPECIFICATIONS AND DOCUMENTS 2

3. INFORMATION TO BE SUPPLIED BY PURCHASER 3

4. ILLUSTRATIONS AND DRAWINGS 3

5. PATENTS 4

6. DEFINITIONS 4

7. MATERIALS, PROCESSES AND FINISHES 27

8. MARKING 27

9. PACKAGING 28

10. QUALIFICATION APPROVAL AND MAINTENANCE OF QUALIFICATION APPROVAL PROCEDURE

28

11. BATCH ACCEPTANCE PROCEDURE 28

12. TEST PROCEDURE 29

13. TEST DETAILS 30

14. SUGGESTION FOR IMPROVEMENT 45

APPENDIX A 46

APPENDIX B 54

FIGURES 56

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0. FOREWORD 0.1 This specification has been prepared by Electronic Components Standardisation Organisation (LCSO) on behalf of Electronic Standardisation Sub Committee on the authority of Standardisation Committee, Ministry Of Defence. 0.2 This specification has been approved by the Ministry of Defence and is mandatory for use by the Defence Services. 0.3 This JSS would be used for design, manufacture, quality assurance and procurement of the item. 0.4 This JSS supersedes JSS 52300: 1975. 0.5 Quality Assurance Authority for the item covered by this Specification is CQA (L) for Army, DRAN for /Navy and DGAQA for Air Force. Enquiries regarding this specification relating to airy contractual conditions should be addressed to the Quality Assurance Authority named in the tender or contract. Other technical enquiries should be referred to: - The Officer-in-Charge LCSO DRDO Complex C.V. Raman Nagar, Bangalore-560 093 0.6 Copies of this specification can be obtained on pay- The Controller Controllerate of Quality Assurance (Electronics) Jayachamrajendra Nagar PO Bangalore -560 006 0.6 This specification holds good only for the supply order for which it is issued. 0.7 This specification holds good only for the supply order for which it is issued.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 1. SCOPE 1.1 This specification relates to the detailed requirements for printed wiring boards, plated through hole consisting of 4 to 10 layers of conductor patterns on insulating bases separated one from the other by an insulating material and interconnected by a continuous metallic interlayer connection. It is to be used in conjunction with JSS 52300 - General requirements for printed wiring boards. 1.2 For the purpose of interpretation or construction in case of any omissions, conflicts, ambiguities or inconsistencies to the extent the contract consists of any or all of the following documents, such documents shall rank in the following order of precedence. (a) Detailed specifications (b) This specification and (c) Other applicable documents 2. RELATED SPECIFICATIONS AND DOCUMENTS 2.1 Joint Services Specifications


- Environmental test methods for Service electronic components.

JSS 50102: 1985 Reaffirmed 2000

- General specification and procedure for the qualification approval and acceptance of electronic components.


- Detailed specification for printed wiring boards, single and double-sided.


- Detailed specification for printed wiring board, multi-layer.


Detailed specification for metal-clad base material (for printed wiring boards of thickness 0.8 mm or greater)

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- Detailed specification for metal-clad base material (for printed wiring boards primarily for multi layer) of thickness less than 0.8 mm

2.2 Other Specifications

IS 9938: 1981 Reaffirmed 1999

Recommended colours for PVC insulation for wires and cables

IS 10673: 1983 Reaffirmed 1996

Sampling plans and procedures for inspection by attributes for electronic items.

2.3 Source of Supplies 2.3.1 Copy of the Joint Services Specifications are obtainable on payment from:- The Controller Controllerate of Quality Assurance (Electronics) JayachamraJendra Nagar PO, Bangalore - 560 006 2.3.2 Copies of Indian Standard are obtainable on payment from :- Bureau of Indian Standards, Manak Bhavan 9, Bahadur Shah Zafar Marg New Delhi = 110 002 Or their regional/branch offices. 3. INFORMATION TO BE SUPPLIED BY THE PURCHASER 3.1 As given in the relevant details specifications. 4. ILLUSTRATIONS AND DRAWINGS 4.1 Dimensions - Dimensions are in millimetres .

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 4.2 Drawings - where drawings are quoted, they are mandatory. Copies of the drawings are obtainable from Officer-in-Charge, LCSO, DRDO Complex, CV Raman Nagar, Bangalore-560 093. 5. PATENTS 5.1 Patents or design rights or copy-rights may subsist in connection with the items defined as standards and the issue of this specification does not convey or imply any licence to use information which is the subject of such rights. 6. DEFINITIONS 6.1 Access Holes - A series in successive layers, each set having a common centre or axis. These holes in a multiplayer printed board provide access to the surface of the land in one of the layers of the board. (See figure 1) 6.2 Activating - A treatment that renders non-conductive material receptive to electroless deposition. (Non-preferred synonyms: "Seeding", "Catalyzing" and "Sensitizing") 6.3 Additive Process - A process for obtaining conductive patterns by the selective deposition of conductive material on the unclad base material. (see also: "Semi-Additive Process" and "Fully-Additive Process") 6.4 Adhesion Promotion - The chemical process of preparing a plastic surface to provide for a uniform, well-bonded metallic overplate. 6.5 Anchoring Spurs - Extensions of lands on flexible printed wiring extending beneath the cover layer to assist in holding the lands to the base material. 6.6 Annular Ring - That portion of conductive material completely surrounding a hole. 6.7 Arc Resistance - The resistance of a material by the effects of a high voltage, low current arc (under prescribed conditions) passing across the surface of the material. The resistance is stated as a measure of total elapsed time required to form a conductive path on the surface (material carbonized by the arc). 6.8 Artwork - An accurately scaled configuration which is used to produce the Artwork Master or Production Waster.

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6.9 Artwork Waster - An accurately-scaled (usually 1:1) pattern which is used to produce the Production Waster. 6.10 Backplane - An interconnection device having terminals (such as solderless wrapped connections) on one side and usually having connector receptacles on the other side, used to provide point-to-point electrical interconnections. The point-to-point electrical interconnections may be printed wiring. (See also "mother board") 6.11 Base Material - The insulating material upon which the conductor pattern may be formed. The base material may be rigid or flexible. It may be a dielectric sheet or insulated metal sheet. 6.12 Base Material Thickness - The thickness of the base material excluding metal foil or material deposited on the surface. 6.13 Basic Dimension - A numerical value used to describe the theoretical exact location of a feature or hole. It is the basis from which permissible variations are established by tolerances on other dimension, in notes or by feature control symbols. 6.14 Bellow Contact - A connector contact which is a flat spring folded to provide a uniform spring rate over the full tolerance range of the mating unit, 6.15 Bent Lead - A lead that is bent either at an approximate 45 degree angle or when used with offset lands is formed to be in direct contact with the land. 6.16 Bifurcated Contact - A connector contact (usually a flat spring) which is slotted lengthwise to provide additional, independently operated points of contact. 6.17 Blank - An unprocessed or partially processed piece of base material or metal-clad base material cut from a sheet or panel and having the rough dimensions of a printed board. 6.18 Bleeding - A condition in which a plated hole discharges process material or solution from crevices or voids. 6.19 Blister - A localized swelling and separation between any of the layers of a laminated base material or between base material and conductive foil (It is a form of delamination). 6.20 Board Thickness - The thickness of the metal-clad base material including conductive layer or layers. (May include additional platings and coatings depending upon when the measurement is made).

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.21 Bond Layer - An adhesive layer used in bonding together other discrete layers of a multilayer printed board during laminations. 6.22 Bond Strength - The force per unit area required to separate two adjacent layers of a board by a force perpendicular to the board surface. (See also: "Peel Strength") 6.23 Bow - The deviation from flatness of a board characterized by a roughly cylindrical or spherical curvature such that if the board is rectangular, its four corners are in the same plane. (See also: "Twist") 6.24 B-staged Resin - A resin in an intermediate state of cure (The cure is normally completed during the laminating cycle). 6.25 Bus Bar - A conduit such as a conductor on a printed board for distributing electrical energy. (A plating Bar is a subcategory of this term) 6.26 Butter-Coat - A commonly used term to describe a higher than usual surface resin. (See also: "Resin-rich"). 6.27 Camber - The planar deflection of a flat cable or flexible laminate from a straight line of specified length. (A flat cable or flexible laminate with camber is similar to the curve of an unbanked race track) 6.28 Capacitive Coupling - The electrical interaction between two conductors caused by allowances. Plated-through holes passing through internal foil planes (ground and voltage) and thermal planes shall meet the same minimum clearance between the plated through hole and foil or ground planes as required for spacing between internal conductors. 6.29 Centre-to-Centre Spacing - The nominal distance between the centres of adjacent features on any single layer of a printed board. (See also "Pitch") 6.30 Circumferential Separation - A crack (1) in the plating extending around the entire circumference of a plated-through hole or (2) in the solder fillet around the lead wire or (3) in the solder fillet around an eyelet or (4) at the interface between a solder fillet and a land. 6.31 Chamfer - A broken corner to eliminate an otherwise sharp edge. 6.32 Characteristic Impedance - The ratio of voltage to current in a propagating wave i.e. the impedance which is offered to this wave at any point of the line. (In printed

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wiring, its value depends on the width of the conductor, the distance from the conductor to ground planets) and the dielectric constant of the media between them) 6.33 Chemical Hole Cleaning - The chemical process for cleaning conductive surfaces exposed within a hole. (See also: "Etchback") 6.34 Clad - A condition of the base material to which a relatively thin layer or a sheet of metal foil has been bonded to one or both of its sides e.g. a metal-clad base material. 6.35 Clearance Hole - A hole in the conductive pattern larger than, but coaxial with, a hole in the printed board base material. 6.36 Clinched Leads - Component leads which extend through the printed board and are formed to effect a spring action, metal-to-metal electrical contact with the conductive pattern prior to soldering. 6.37 Clinched-Wire Through Connection - Connection made by a wire which is passed through a hole in a printed board and subsequently formed or clinched, in contact with the conductive pattern on each side of the board and soldered. 6.36 Cold Solder Joint - Solder connection exhibiting poor wetting and a grayish, porous appearance due to insufficient heat, inadequate cleaning prior to soldering or due to excessive impurities in the solder solution. 6.39 Component Density - The quantity of components on a printed board per unit area. 6.40 Component Lead - The solid or stranded wire or formed conductor that extends from a component and service as a mechanical or electrical connection or both. 6.41 Component Hole A hole used for the attachment and electrical connection of component terminations including pins and wires to the printed board. 6.42 Component Side - That side of the printed board on which most of the components will be mounted. 6.43 Conductive Foil - A thin sheet of metal that may cover one or both sides of the base material. (Includes conductor, lands and through connections when these connections are an integral part of the manufacturing process)

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.44 Conductive Pattern - The configuration or design of the conductive material on the base material. (Includes conductors, lands and through connections when these connections are an integral part of the manufacturing process) 6.45 Conductor - A single conductive path in a conductive pattern. 6.46 Conductor Base Width - The conductor width at the plane of the surface of the base material. (See also: "Conductor Width" and "Design Width of Conductor") 6.47 Conductor Layer - The total conductive pattern formed upon one side of a single layer of base material. 6.48 Conductor Layer No.l - The first layer having a conductive pattern, of a multilayer printed board, on or adjacent to the component side. 6.49 Conductor Side - The side in a single sided printed board containing the conductive pattern. 6.50 Conductor Spacing - The distance between adjacent edges (not center line to center line) of isolated conductive patterns in a conductor layer. 6.51 Conductor Thickness - The thickness of the conductor including all metallic coatings. (It excludes non-conductive protective coating) 6.52 Conductor Width - The observable width of a conductor at any point chosen at random on the printed board, normally viewed from vertically above unless otherwise specified. (Imperfections for example nicks, pinholes or scratches allowable by the relevant specification shall be ignored. (See also a "Design Width of Conductor" and "Conductor Base Width") 6.53 Conductor to Hole Spacing - The distance between the edge of a conductor and the edge of a supported or unsupported hole. 6.54 Conformal Coating - An insulating protective coating, which conforms to the configuration of the object coated, applied o the completed board assembly. 6.55 Connector Area - That portion of printed wiring used or the purpose of providing external electrical connections. 6.56 Contact Area - The common area between a conductor and connector through which the flow of electricity takes place.

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6.57 Contact Resistance - The electrical resistance of the metallic surfaces at their interface in the contact area under specified conditions. 6.58 Contact Spacing - The distance between the centerlines of adjacent contact areas. 6.59 Continuity - An uninterrupted path for the flow of electrical current in a circuit. 6.60 Corner Mark (Crop Mark) - The mark at the corners of a printed board artwork, the inside edges of which usually locate the borders and establish the contour of the board. 6.61 Cover Lay, Cover Layer, Cover Coat - An outer layer(s) of insulating material applied over the conductive pattern on the surface of the printed board. 6.62 Cracking - A condition consisting of breaks in metallic or non-metallic coatings or both that extend through to an underlying surface. 6.63 Crazing - An internal condition occurring in the laminated base material in which the glass fibres are separated from the resin at the weave intersections. This condition manifests itself in the form of connected white spots or "crosses below the surface and the base material and is usually related to mechanically induced stress. 6.64 Crazing (Conformal Coating) - A network of fine cracks on the surface or within the conformal coating. 6.65 Crosshatching - The breaking of large conductive areas by the use of a pattern of voids in the conductive material. 6.66 Crosstalk - The undesirable interface caused by the coupling of energy between signal paths. 6.67 Current-carrying Capacity - The maximum current which can be carried continuously, under specified conditions, by a conductor without causing objectionable degradation of electrical or mechanical properties of the printed board. 6.68 Datum Reference - A defined point, line or plane used to locate the pattern or layer for manufacturing, inspection or for both purposes. 6.69 Delamination - A separation between plies within the base material or between the base material and the conductive foil or both.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.70 Dent - A smooth depression in the conductive foil which does not significantly decrease foil thickness. 6.71 Design Midth of Conductor - The width of a conductor as delineated or noted on the master drawing. 6.72 Device - an individual electrical element, usually in an independent body, which cannot be further reduced without destroying its stated function. 6.73 Dewetting - A condition which results when molten solder has coated a surface and then receded leaving irregularly shaped mounds of solder separated by areas covered with a thin solder film, base metal is not exposed. 6.74 Dielectric Breakdown - A complete failure of a dielectric material characterized by a disruptive electrical discharge through the material due to a sudden and large increase in voltage. 6.75 Dielectric Constant - The ratio of the capacitance (C) of a given configuration of electrodes with a specified dielectric to the capacitance


Diss. Fac. = power loss ----------------------------- E x f x volume x constant 6.82 Double-Sided Board - A printed board with a conductive pattern on both sides. 6.83 Drag Soldering - A process whereby supported moving printed circuit assemblies or printed wiring assemblies are brought in contact with the surface of a static pool of molten solder. 6.84 Dross - Oxide and other contaminants which form on the surface of molten solder. 6.85 Dual In-Line Package (DIP) - A component which terminates in two straight tows of pins or lead wires. 6.86 Edge-Board Connector - A connector designed specifically for making removable and reliable interconnections between the edge board contacts on the edge or a printed board and external wiring. 6.87 Edge-Board Contacts - A series of contacts printed on or near any edge of a printed board and intended for mating with an edge-board connector. 6.88 Edge Definition - The fidelity of reproduction of a pattern edge relative to the production master. 6.89 Edge Spacing - The distance of a pattern, components or both from the edges of the printed board. 6.90 E Glass - A low alkali lime alumina borosilicate glass, noted for its good electrical properties. (It has the following chemical formulation in percentage by mass. B2O3 5-10%, CaO 16-25%., Al2O3 12-16%.,SiO2 52-56%, NaO2 and K2O 0-2%., TiO2 0-0.8%., Fe2O3 0.05-0.4%., F2 0-1.0%) 6.91 Electroless Deposition - The deposition of metal from an autocatalytic plating solution without application of electrical current. 6.92 Electrodeposition - The deposition of a conductive material from a plating solution with application of electrical current. (Non-preferred synonyms: "Electrolytic deposition" and "Galvanic deposition")

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.93 Etchant - A solution used to remove by chemical reaction, the unwanted portion of material from a printed board. 6.94 Etchback - A process for the controlled removal of nonmetallic materials from sidewalls of holes to a specified depth. It is used to remove resin smear and to expose additional internal conductor surfaces. 6.95 Etch Factor - The ratio of the depth of etch (conductor thickness) to the amount of lateral etch. (Undercut). 6.96 Etched - Etching - Printed Board - A board having a conductive pattern farmed by the chemical removal of unwanted portions of the conductive foil. 6.97 Etching - A process wherein a printed pattern is formed by chemical, or chemical and electrolytic removal of the unwanted portion of conductive material bonded to a base. 6.98 Etching Indicator - A wedge shaped or other specified pattern affixed to the conductive foil to indicate the quantity of etching. 6.99 Extraneous Copper - Unwanted copper remaining on the base material after chemical processing. 6.100 Eyelet - A hollow tube inserted in a terminal or printed board to provide mechanical support for component leads or electrical connection. 6.101 Fibre Exposure - A condition in which reinforced fibres within the base material are exposed in machined, abraded or chemically - attacked areas. 6.102 Flat Cable - A cable with two or more parallel, round or flat conductors in the same plane encapsulated by an insulating material. 6.103 Flexible Printed Circuit - A random arrangement of printed circuit and components utilizing flexible base material with or without flexible cover layers. 6.104 Flexible Printed Miring - A random arrangement of printed wiring utilising flexible base material with or without flexible cover layers, 6.105 Flexural Failure - A conductor failure caused by repeated flexing. It is indicated by an increase of resistance measured for a specified time. 6.106 Flush Conductor - A conductor whose outer surface is in the same plane as the surface of the insulating material adjacent to the conductor.

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6.107 Flux - A chemically active compound that is capable of promoting the Metting of metals with solder. 6.108 From-to-List - Written wiring instructions in the form of a list indicating termination points. 6.109 Fully-Additive Process (non-preferred synonym: Fully Electroless) - An additive process wherein the entire thickness of electrically isolated conductors is built-up by electroless metal deposition. 6.110 Fused Coating - A metallic coating (usually tin or solder alloy) which has been melted and solidified forming a metallurgical bond to the base metal. 6.111 Fusing - The melting of a metallic coating (usually electro-deposited), followed by solidification. 6.112 Gel Time - The time expressed in seconds, required for a resin to change its physical state from a solid through a liquid to a solid again due to the action of thermal input. 6.113 Glass Transition Temperature - The temperature at which an amorphous polymer (or the amorphous regions in a partially crystalline polymer) changes from a hard and relatively brittle condition to a viscous or rubbery condition. (This transition generally occurs over a relatively narrow temperature range; it is not a phase transition. In this temperature region, many physical properties undergo significant rapid changes. Some of these properties are hardness, brittleness, thermal expansion, specific heat etc.). 6.114 Grid - An orthogonal network of two sets of parallel equidistant lines used for locating points on a printed board, 6.115 Ground Plane - A conductor layer or portion of a conductor layer (usually a continuous sheet of metal with suitable ground plane clearances), used as a common reference point for circuit returns, shielding or heat sinking. 6.116 Ground Plane Clearance - Ground-plane clearance is the etched portion of a ground plane around a plated-through or non-plated through hole that isolates the plane from the hole. 6.117 Haloing - Mechanically induced fracturing or delaminating on or below the surface of the base material; it is usually exhibited by a light area around holes, other machined areas or both.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.118 Heat Sinking Plane - A continuous sheet of metal on or in a printed board that functions to dissipate heat away from heat sensitive components. 6.119 Hole Breakout - A condition in which a hole is not completely surrounded by the land. 6.120 Hole Density - The quantity of holes in a printed board per unit area. 6.121 Hole Location - The dimensional location of the center of a hole per unit area. 6.122 Hole Pattern - The arrangement of all holes in a printed board. 6.123 Hole Pull Strength - The force necessary to rupture a plated through hole when loaded or pulled in the direction of the axis of the hole. 6.124 Hole Void - A void in the metallic deposit of a plated through hole exposing the base material. 6.125 Immersion plating (Galvanic Displacement) - The chemical deposition of a thin metallic coating over certain base metals by a partial displacement of the base metals. 6.126 Inclusion - A foreign particle, metallic or non-metallic, in a conductive layer, plating or base material. 6.127 Insulation Resistance - The electrical resistance of the insulating material (determined under specified conditions) between any pair of contacts, conductors or grounding devices in various combinations. 6.128 Interlayer Connection - An electrical connection between conductive patterns in different layers of a multilayer printed board. 6.129 Internal Layer - A conductive pattern which is contained entirely within a multilayer printed board. 6.130 Interstitial via Hole - A plated-through hole connecting two or more conductor layers of a multilayer printed board but not extending fully through all the layers of base material comprising the board. 6.131 lonizable Contaminants - Process residues such as flux activators, finger prints, etching and plating salts etc. that exist as ions and when dissolved increase electrical conductivity.

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6.132 Jumper - An electrical connection between two points on a printed board added after the intended conductive pattern is formed. 6.133 Jumper Wire - A wire used as a Jumper. 6.134 Key - A device designed to assure that the coupling of two components can occur in only one position. 6.135 Keying Slot - A slot in a printed board which permits the printed board to be plugged into its matting receptacle but prevents it from being plugged into any other receptacle. 6.136 Keyway - A general term covering both keying slot(s) and polarizing slot(s). 6.137 Laminate - A product made by bonding together two or more layers of material. 6.136 Laminate Thickness - Thickness of the metal-clad base material, single or double-sided, prior to any subsequent processing. 6.139 Land - A portion of a conductive pattern usually, but not exclusively, used for the connection or attachment of components or both. 6.140 Landless Hole - A plated-through hole without a land(s). 6.141 Layer-to-Layer Spacing - The thickness of dielectric material between adjacent layers of conductive circuitry in a multilayer printed board. 6.142 Lead Projection - The distance which a component lead protrudes through the printed board on the side opposite from which the component is mounted. 6.143 Legend - A format of letters, numbers, symbols and patterns on the printed board primarily used to identify component locations and orientation for convenience in assembly and replacement operations. 6.144 Margin - The distance between the reference edge of a flat cable and the nearest edge of the first conductor. 6.145 Marking - A method of identifying printed boards with part number, revision letter, manufacturer's code etc. 6.146 Master Drawing - A document that shows the dimension limits or grid locations applicable to any or all parts of a printed board (rigid or flexible) including the

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 arrangement of conductive and nonconductive patterns of elements, size, type, and location of holes and any other information necessary to describe the product to be fabricated. 6.147 Mealing - A condition at the interface of the conformal coating and base material; it is in the form of discrete spots or patches which reveal separation of the conformal coating from the surface of the printed boards or from the surfaces of attached components or from both. 6.148 Measling - An internal condition occurring in laminated base material in which the glass fibers are separated from the resin at the weave intersection. This condition manifests itself in the form of discrete white spots or "crosses" below the surface of the base material and is usually related to thermally induced stress. 6.149 Metal-clad Base Material - Base material covered with foil on one or both of its sides. 6.150 Metallization - A deposited or plated thin metallic film used for its protective or electrical properties. 6.151 Microstrip - A type of transmission line configuration which consists of a conductor over a parallel ground plane and separated by a dielectric. 6.152 Microsectioning - The preparation of a specimen for the microscopic examination of the material to be examined, (usually by cutting out a cross-section followed by encapsulation, polishing, etching, staining etc.) 6.153 Minimum annular Ring - The minimum width of metal, at the narrowest point, between the edge of the hole and the outer edge of the land. This measurement is made to the drilled hole on internal layers of multilayer printed boards and to the edge of the plating on outside layers of multilayer boards and double sided boards. 6.154 Minimum Electrical Spacing - The minimum allowable distance between adjacent conductors that is sufficient to prevent dielectric breakdown or corona or both, between the conductors at any given voltage and altitude. 6.155 Misregistration - The lack of dimensional conformity between successively produced features or patterns. 6.156 Module - A separable unit in a packaging scheme displaying regularity of dimensions.

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6. 157 Mother Board - A printed board assembly used for interconnecting arrays of plug-in electronic modules. 6.158 Mounting Hole - A hole used for the mechanical mounting of a printed board or for the mechanical attachment of components to the printed board. 6.159 Multilayer Printed Board - The general term for completely processed printed circuit or printed wiring configurations consisting of alternate layers of conductive patterns and insulating materials bonded together, with conductive patterns in more than two layers and with the conductive patterns interconnected as required. The term includes both flexible and rigid multilayer boards. 6.160 Multilayer Printed Board, Sequentially Laminated - A multilayer board which is formed by laminating through-hole-plated double sided or multilayer boards together. The circuitry layers are interconnected with interstitial via holes and through connections. 6.161 Multilayer Printed Circuit Board - A part manufactured from rigid base material upon which a completely processed printed circuit has been formed on more than two layers, each separated by insulating material and bonded together. 6.162 Multilayer Printed Miring Board - A part manufactured from rigid base material upon which completely processed printed wiring has been formed on more than two layer, each separated by insulating materials and bonded together. 6.163 Nail Heading - The flared condition of copper on the inner conductor layers of a multilayer board caused by hole drilling. 6.164 Negative - An artwork, art workmaster or production master in which the intended conductive pattern is transparent to light and the areas to be free from conductive material are opaque. 6.165 Negative Etchback - Etchback in which inner conductor layer of material is recessed relative to the surrounding base material. (See Figure 12) 6.166 Negative-acting Resist - A resist which is polymerized (hardened) by light and which, after exposure and development, remains on the surface of a laminate in those areas which were under the transparent parts of a production master. 6.167 Nonconductive Pattern - A configuration formed by functional nonconductive material of a printed circuit, (e.g. dielectric, resist etc.) 6.168 Nonfunctional Land - A land on internal or external layers not connected to the conductive pattern on its layer.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.169 Nonpolar Solvents - Solvents which are not ionized sufficiently to be electrically conductive and which cannot dissolve polar compounds such as inorganic salts but can dissolve nonpolar compounds such as hydrocarbons and resins. 6.170 Nonwetting - A condition whereby a surface has contacted molten solder but the solder has not adhered to all of the surface and base metal remains exposed. 6.171 Offset Land - A land which is intentionally not in physical contact with its associated component hole. 6.172 Opaquer - A material that when added to the resin systems renders a laminate sufficiently opaque so that the yarn or weave of the reinforcing material cannot be seen with the unaided eye using either reflected or transmitted light. 6.173 Outgassing - De-aeration or other gaseous emission from a printed board assembly (printed board, component or connection) when exposed to a reduced pressure or heat or both 6.174 Outgrowth - The increase in conductor width at one side of a conductor caused by plating build-up, over that delineated on the production master. 6.175 Overhang - The sum of outgrowth and undercut. (If undercut does not occur, the overhang is the outgrowth only) 6.176 Packaging Density - Quantity of functions (components, interconnection devices, mechanical devices) per unit volume usually expressed in qualitative terms such as high, medium or low. 6.177 Panel - A rectangular or square base material of predetermined size intended for or containing one or more printed boards and when required, one or more test coupons. 6.178 Panel Plating - The plating of the entire surface of a panel (including holes). 6.179 Pattern - The configuration of conductive and non-conductive materials on a panel or printed board. (Pattern denotes also the circuit configuration on related tools, drawings and masters) 6.180 Pattern Plating - The selective plating of a conductive pattern. 6.181 Peel Strength - The force per unit width required to peel the conductor or foil from the base material.

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6.182 Permanent Mask - A resist which is not removed after processing (e.g. plating resist used in the fully additive process) 6.183 Photographic Reduction Dimension - Dimensions (e.g. the distance between lines or between two specified points) on the artwork master to indicate to the photographer the extent to which the artwork master is to be photographically reduced, (The value of the dimension refers to the HI scale and must be specified) 6.184 Pin Density - The quantity of pins on a printed board per unit area. 6.185 Pinhole - A small hole occurring as an imperfection which penetrates entirely through a layer of material. 6.186 Pit - A depression in the conductive layer that does not penetrate entirely through it. 6.187 Pitch - The nominal distance from centre-to-centre of adjacent conductors. (Where conductors are of equal size and spacing is uniform, the pitch is usually measured from the reference edge of a conductor to the reference edge of the adjacent conductor) 6.188 Plate Finish (pertaining to laminating) - The finish present on the metallic surface of metal-clad base material resulting from direct contact with the laminating press plates without modification by any subsequent finishing process. 6.189 Plated Through Hole - A hole in which electrical connection is made between internal or external conductive patterns or both, by the deposition of metal on the wall of the hole. 6.190 Plated-Through Hole Structure Test - A visual examination of the metallic conductors and plated-through holes of a printed board after the glass-plastic laminate has been dissolved away. 6.191 Plating Bar - The temporary conductive path interconnecting areas of a printed board to be electroplated, usually located on the panel outside of the borders of such a board. 6.192 Plating Up - The process consisting of the electrochemical deposition of a conductive material on the base material (surface holes etc.) after th6 base material has been made conductive. 6.193 Plotting - The practice of mechanically converting X-Y positional information into a visual pattern such as artwork.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.194 Polarisation - A technique of eliminating symmetry within a plane so that parts can be engaged in only one way in order to minimize the possibility of electrical and mechanical damage or malfunction. 6.195 Polarizing Slot - A slot at the edge of a printed board, used to assure proper insertion and location in a mating connector. 6.196 Polar Solvents - Solvents which are ionized sufficiently to be electrically conductive and which can dissolve polar compounds such as inorganic salts but cannot dissolve nonpolar compounds such as hydrocarbons and resins. 6.197 Positive - An artwork, artwork master or production master in which the intended conductive pattern is opaque to light and the areas intended to be free from conductive material are transparent. 6.198 Positive-acting Resist - A resist which is decomposed (softened) by light and which, after exposure and development, is removed from those areas which were under the transparent parts of a production master. 6.199 Prepreg - Sheet material (e.g. glass fabric) impregnated with a resin cured to an intermediate stage. (B-stage resin) 6.200 Press-fit Contact - An electrical contact which can be pressed into a hole in an insulator, printed board (with or without plated-through holes) or a metal plate. 6.201 Printed Board - The general tern) for completely processed printed circuit or printed wiring configurations. It includes rigid or flexible, single, double, and multiplayer boards. 6.202 Printed Circuit - A conductive pattern comprised of printed components, printed wiring or a combination thereof, all formed in a predetermined design and intended to be attached to a common base. (In addition, this is a generic term used to describe a printed board produced by any of a number of techniques) 6.203 Printed Circuit Board - A part manufactured from rigid base material upon which a completely processed printed circuit has been formed. 6.204 Printed Component - A part such as an inductor, resistor, capacitor or transmission line which is formed as part of the conductive pattern of the printed board. 6.205 Printed Contact - A portion of a conductive pattern formed by printing, serving as one part of a contact system.

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6.206 Printed Miring - The conductive pattern intended to be formed on a common base to provide point-to-point connection of discrete components but not to contain printed components. 6.207 Printed Wiring assembly Drawing - A document that shows the printed board (rigid or flexible), the separately manufactured components which are to be added to the board and any other information necessary to describe the joining of these parts to perform a specific function. 6.208 Printed Miring Board - A part manufactured from rigid base material upon which completely processed printed wiring has been formed. 6.209 Printed Wiring Layout - A sketch that depicts the printed wiring substrate, the physical size and location of electronic and mechanical components and the outing of conductors that electrically interconnect components, in sufficient detail to allow the preparation of documentation and artwork. 6.210 Production master -A 1 to 1 scale pattern which is used to produce one or more printed boards (rigid or flexible) within the accuracy specified on the Waster drawing. 6.210.1 Single-Image Production Waster - A production master used in the process for making a single printed board. 6.210.2 Multiple - Image Production Master - A production master used in the process for making two to more printed boards simultaneously. 6.211 Reference Edge - The edge of cable or conductor from which measurements are made (Sometimes indicated by a thread, identification stripe, or printing). Conductors are usually identified by their sequential position from the reference edge with number one conductor closest to this edge. 6.212 Reflow Soldering - process for Joining parts by finning the mating surfaces, placing them together, heating until the solder fuses and allowing to cool in the joined position. 6.213 Register Mark - symbol used as a reference point to maintain registration. 6.214 Registration - The degree of conformity of the position of a pattern or a portion thereof, with its intended position or with that of any other conductor layer of a board.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.215 Repairing - The act of restoring the functional capability of a defective part without necessarily restoring appearance, interchangeability and uniformity. 6.216 Resin Recession - The presence of voids between the barrel of the plated-through hole and the wall of the hole, seen in micro sections of plated-through holes in boards that have been exposed to high temperatures. 6.217 Resin-rich - Significant thickness of non-reinforced surface-layer resin of the same composition as that within the base material. 6.218 Resin Smear - Resin transferred from the base material onto the surface or edge of the conductive pattern normally caused by drilling. 6.219 Resin Starved area - In area in a printed board that has an insufficient amount of resin to wet out the reinforcement completely evidenced by low gloss, dry spots or exposed fibres. 6.220 Resist - Coating material used to mask or to protect selected area of a pattern from the action of an etchant, solder or plating. 6.221 Resistance Soldering - Method of soldering in which a current is passed through and heats the soldering area by contact with one or more electrodes- 6.222 Reverse Image - The resist pattern on a printed board used to allow for the exposure of conductive areas for subsequent plating. 6.223 Reversion - Chemical reaction in which a polymerized material degenerates at least partially, to a lower polymeric state or the original monomer. It is usually accompained by significant changes in physical and mechanical properties. 6.224 Reworking - The act of repeating one or more manufacturing operations for the purpose of improving the yield of acceptable parts. 6.225 Right-angle Edge Connector - Connector which terminates conductors at the edge of a printed board while bringing the terminations out at right angle to the plane of the board conductors. 6.226 Roadmap - Printed pattern of non-conductive material by which the circuitry and components are delineated on a board to aid in service and repair of the board. 6.227 Schematic Diagram - Drawing which shows, by means of graphic symbols, the electrical connections, components and functions of a specific circuit arrangement.

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6.228 Screen Printing (non-preferred synonym: Silk Screening) A process for transferring an image to a surface by forcing suitable media through a stencil screen with a squeeze. 6.229 Semi-Additive Process - An additive process for obtaining conductive patterns which combines an electroless metal deposition on an unclad substrate with electroplating, etching or with both, 6.230 Separable Component Part - Replaceable component part, the body of which is not chemically bonded (excluding protective, coatings, solder and potting materials) to the base material. 6.231 Shadowing -Condition occurring during etchback in which the dielectric material, immediately next to the foil, is incompletely removed although acceptable etchback may have been achieved elsewhere. 6.232 Shielding, Electronic - % physical barrier usually electrically conductive designed to reduce the interaction of electric or magnetic fields upon devices, circuits or portions of circuits. 6.233 Signal - An electrical impulse of a predetermined voltage, current, polarity and pulse width. 6.234 Single Conductor - An individual conductor used to transmit an impressed signal. 6.235 Signal Plane - A conductor layer intended to carry signals rather than serve as a ground or other fixed voltage function. 6.236 Single Sided Board - A printed board with a conductive pattern on one side only. 6.237 Solder Plugs - Cores of solder in the plated-through holes of a printed board. 6.238 Solder Projection - An undesirable protrusion of solder from a solidified solder joint or coating. 6.239 Solder Side - The side of a printed board which is opposite to the component side. 6.240 Solderability - The property of a metal to be wetted by solder.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.241 Soldering - The process of joining metallic surfaces with solder without melting of the base material. 6.242 Solderless Wrap - A method of connecting a solid wire to a square, rectangular or V-shaped terminal by tightly wrapping the wire around the terminal with a special tool. 6.243 Span - The distance from the reference edge of the first conductor to the reference edge of the last conductor, expressed in decimal inches or centimetres. 6.244 Stamped Printed Miring - Miring which is produced by die stamping and which is bonded to an insulating base. 6.245 Step and Repeat - A method by which successive exposures of a single image are made to produce a Multiple Image Production Master. 6.246 Step-Scale Step-Wedge - A series of regularly spaced tones ranging from clear to black through intermediate shades of grey and used as a reference scale for exposure control in photo fabrication. 6.247 Stripline - A type of transmission line configuration which consists of a single narrow conductor parallel and equidistant to two parallel ground planes. 6.248 Subtractive Process - A process for obtaining conductive patterns by the selective removal of unwanted portions of a conductive foil. 6.249 Supported Hole - A hole in a printed board that has its inside surface plated or otherwise reinforced. 6.250 Surface Mounting - The electrical connection of components to the surface of a conductive pattern without utilizing component holes. 6.251 Swaged Leads - Component lead wires which extend through the printed board and are flattened or swaged so as to secure the component to the board during manufacturing operations. 6.252 Taped Components - Components attached to a continuous tape for and in automatic assembly. 6.253 Tenting - A printed board fabrication method of covering over plated-through holes and the surrounding conductive pattern with a resist, usually dry film.

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6.254 Test Board - A printed board suitable for determining acceptability of the board or of a batch of boards produced with the same process so as to be representative of the production board. 6.255 Test Coupon - A portion of a printed board or of a panel containing printed coupons used to determine the acceptability of such a board (s). 6.256 Test Pattern - A pattern used for inspection or testing purpose. 6.257 Test Point - Special points of access to an electrical circuits used for testing purposes. 6.258 Thermal Relief - Crosshatching to minimize blistering or warping during soldering operations. 6.259 Thief - A racking device used in the electroplating process to provide a more uniform current density on plated parts. ("Thieves absorb the unevenly distributed current on irregularly shaped parts, thereby; assuring that the parts will receive an electroplated coating of uniform thickness) 6.260 Through Connection - An electrical connection between conductive patterns on opposite sides of an insulating base e.g. plated through hole or clinched jumper wire. 6.261 Thin Foil - A metal sheet less than 0.0178 mm thick. 6.262 Tinning - A process for the application of solder coating on component leads, conductors and terminals to enhance solderability. 6.263 Tooling Feature - A specified physical feature on a printed board or a panel such as a marking, hole, cut-out, notch, slot or edge used exclusively to position the board or panel or to mount components accurately. 6.264 Tooling Holes - The general term for holes placed on a printed board or a panel and used to aid in the manufacturing process, 6.265 Transmission Cable - Two or more transmission lines. (If the structure is flat, it is called "flat-transmission cable" to differentiate it from a round structure such as a jacketed ground of coaxial cables) 6.266 Transmission Line " A signal-carrying circuit composed of conductors and dielectric material with controlled electrical characteristics used for the transmission of high-frequency or narrow pulse type signals.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 6.267 Treatment Transfer - The transfer of copper foil treatment to the base material as indicated by the presence of black, brown or red streaks after the copper has been removed by etching, 6.268 Trim Lines - Lines which define the borders of a printed board. 6.269 True Position - The theoretically exact location of a feature or hole established by basic dimension. 6.270 True Position Tolerance - The total diameter of permissible movement around the true position as shown in the master drawing. 6.271 Twist - The deformation parallel to a diagonal of rectangular sheet such that one of the corners is not in the plane containing the other three corners. 6.272 Undercut (in process) - The distance on one edge of a conductor measured parallel to the board surface from the outer edge of the conductor including etch resists, to the maximum point of indentation on the copper edge. 6.273 Undercut (after fabrication) - The distance on one edge of a conductor measured parallel to the board surface from) the outer edge of the conductor excluding overplating and coating, to the maximum point of indentation on the same edge. 6.274 Underwriters Symbol - Pt logotype authorised for placement on a product which has been recognized (accepted) by Underwriters Laboratories, Inc, (UL). 6.275 Unsupported Hole - A hole containing no conductive material nor any other type of reinforcement. 6.276 Via Hole - A plated-through hole used as a through connection, but in which there is no intention to insert a component lead or other reinforcing material. 6.277 Void - The absence of substances in a localized area. 6.278 Voltage Plane - A conductor or portion of a conductor layer on or in a printed board which is maintained at other than ground potential. It can also be used as a common voltage source for heat sinking or for shielding. 6.279 Voltage-plane clearance - Voltage-plane clearance is the etched portion of a voltage plane around a plated-through or non-plated through hole that isolates the voltage plane from the hole.

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6.280 Wave Soldering - A process wherein printed boards are brought in contract with the surface of continuously flowing and circulating solder. 6.281 Meave Exposure - A surface condition of base material in which the unbroken fibres of woven glass cloth are not complete covered by resin. 6.282 Weave Texture - A surface condition of base material in which a weave pattern of glass cloth is apparent although the unbroken fibers of the woven cloth are completely covered with resin. 6.283 Metting - The formation of a relatively uniform, smooth, unbroken and adjacent film of solder to a base material. 6.284 Whisker - A slender acicular (needle shaped) metallic growth on a printed board. 6.285 Wicking - Capillary absorption of liquid along the fibres of the base material. 7. MATERIALS, PROCESSES AND FINISHES 7.1 Where materials, processes and finishes are specified in the relevant detailed specifications, they are mandatory, attention is drawn to the requirements in JSS 50102 that materials, processes and finishes shall not be changed significantly without prior approval. 7.2 Workmanship, Processor and Finishes - Printed wiring boards shall be processed in such a manner as to be uniform in quality and shall be free from dirt, oil, corrosion, corrosive products, salts, smut, grease, finger prints, mould release agents, foreign matter, flux residue and other defects that will affect life, serviceability or any combination of these. 8. MARKING 8.1 Each board shall be legibly and indelibly marked with the date, manufacturers code and serial number. The marking shall be produced either by the same process used in producing the conductor pattern or by use of a permanent non-nutrient ink or paint. Conductive Marking shall not be closer to the pattern than the spacing requirement specified. All markings shall be compatible with materials and parts, legible after all tests and in no case shall affect the board performance.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 9. PACKAGING 9.1 Printed wiring boards shall be clear dry and packed in a manner that will afford adequate protection against corrosion, deterioration and physical damage. Shipment Packaging (preservation, identification and picking) shall be in accordance with the terms of the contract. 10. QUALIFICATION APPROVAL AND MAINTENANCE OF

QUALIFICATION APPROVAL PROCEDURE 10.1 Qualification Approval and Maintenance of Qualification Approval shall be obtained as described in JSS 50102 and in the relevant detailed specification. 10.2 Provision of Samples - The manufacturer shall, submit specimens of printed wiring boards for which approval is desired, as specified in the relevant detailed specification. 10.3 Grouping of Specimens - The test specimens shall be grouped as indicated in the relevant detailed specification. 10.4 Test incidence - Initial measurements referred to in Table 4 of JSS 50101 and in this specification as Group '0', shall be carried out immediately prior to the commencement of tests on subsequent groups and the results shall be recorded. Each test shall be performed in the order listed and where measurements are not required, the results shall be recorded where tests are not applicable, this will be indicated in the relevent detailed specification. 11. BATCH ACCEPTANCE PROCEDURE 11.1 Batch acceptance shall be performed as described in JSS 50102 and in this specification. 11.2 Inspection Batch - Unless otherwise specified in the relevant detailed specification, an inspection batch shall be as specified in IS 10&73 and shall consist of printed wiring boards of the same style produced under essentially the same conditions and offered for inspection at one time. Each production board or panel of boards shall incorporate the test coupons at specified. The location of the test coupons shall be not closer to the edge of the panel than the edge of the printed wiring board. Test coupons shall be used in performing Group A' inspection and all unused test coupons shall be retained by the supplier, unless otherwise specified.

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11.3 100 percent Acceptance Test - These tests shall be performed as described in the relevant detailed specifications. 11.4 Sampling Tests - Tests bracketed together within a group or subgroup are considered as a sequence and must be performed as such using the same sample. 11.4.1 Group 'A' Tests - These tests shall be performed as described in the relevant detailed specifications. 11.4.2 Group 'B' Tests - These tests shall be performed as described in the relevant detailed specifications. 12. TEST PROCEDURE 12.1 Atmospheric Condition for Testing - Unless otherwise specified, all tests shall be performed under standard atmospheric conditions as defined in JSS 50101. 12.2 Accuracy of Test Equipment - The accuracy of test equipment shall be as specified in the relevant test clauses.

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 13. TEST DETAILS

13.1 Wherever, the terms 'as specified' occurs against the 'description' or 'requirements' it indicates that details are given in the corresponding clauses of the relevant detailed specifications.

Test Number

Title of Test Description Requirements

1 2 3 4 13.1 General

Examination

13.1.1 Visual Examination

The boards shall be examined visually to verify that the dimensions, machinability, repair, marking and workmanship are in accordance with the applicable requirements. Suitable light source and magnification (approximately 3x) shall be employed. For acceptance test, reference shall be made to qualification approval certificate for compliance.

The board shall be processed in such a manner as to be uniform oil, corrosion corrosive products salts, grease, finger prints, mould release agents, foreign matter and other defects that will affect life, serviceability and appearance (See also clause 7). Marking shall be in accordance with the Master Drawing and shall be made either by the same process used in producing the conductor pattern or with the use of percent ink or paint. Conductive marking shall not be closer to the pattern than the, spacing, requirements, given in Appendix, 'A'. Marking shall be legible and shall in no case affect the performance of board (See also clause 8). The board shall be capable of withstanding in all directions in required machine operation, without cracking, splitting, delaminating or in any other way exhibiting adverse effects.

The burrs, nicks along the edges of Printed Wiring Boards shall be acceptable provided the penetration does not reduce edge spacing more than 50% of the edge spacing specified in the Master Drawing. The penetration shall not exceed 2.5 mm if it is not mentioned in the Master Drawing.

13.1.1.1 Edge of the printed Wiring Board

The edge of the Printed Wiring Boards shall be inspected to verify burrs, nicks and haloing along the edges of Printed Circuit Board.

30


Test Number


1 2 3 4 13.1.1.2 Surface

Imperfection The features of the boards shall be inspected using an optical apparatus or aid which provides a minimum magnification of 4X. Inspection of Board features shall be accomplished at a magnification of 10X.

Surface imperfection (such as weave texture, haloing, scratches pits and dents shall be acceptable if: a) The laminate fibre is not cut. b) The imperfection does not bridge between conductors.

c) The dielectric spacing between the imperfection and a conductor is not reduce below the minimum requirements i.e. 0.13 mm for external conductors and 0.10 mm for internal conductors. And the minimum laternal width of external and internal conductors shall not be less the 0.13 mm.

13.1.1.3 Sub-surface Imperfection

The PWBs shall be inspected as specified in clause 13.1.1.2

The blistering, haloing and delamination shall be acceptable provided:

a) Imperfection is tranclucent.

b) It does not bridge more than 25% ofthe distance between conductors or plated through holes. Not more than one percent of the board area on each side shall be affected.

c) Does not reduce conductor spacing below the minimum requirements as mentioned in clause 13.1.1.2. d) Does not propagate as a result of testing (such as bond strength, rework simulation, thermal stressor thermal shock).

13.1.1.4 Repair The PWBs shall be inspected as specified in clause 13.1.1.1

There shall be no evidence of repair when inspected and PW shall not be repaired.

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Test Number


1 2 3 4 13.1.2 Dimensions and

Materials The dimensions of the board and pattern shall be checked for conformity with the Master Drawing. The finished Printed Wiring Board shall meet the dimensional requirements specified here in an on the Master Drawing.

The dimensions of the board and pattern shall be specified on the Master Drawing. The type of Material shall be as given below and as specified in the drawing: a) For Single and Double sided boards: The metal clad laminates shall be in accordance with JSS 51701. b) For multiplayer boards: - The metal clad laminates shall be in accordance with JSS 51702 and of a type specified on the relevant Drawing. Base material shall be of minimum 0.05 mm per sheet. Copper cladding on external surface, shall be at least 305 g/ m and copper cladding on internal layers shall be at least 610 g/m. The bonding interlayer material shall be a pre-impregnated glass cloth. There shall be a minimum of 0.1 mm of dielectric material between conductive layers of Copper in the finished board.

13.1.2.1 Annular ring The measurement of the annular ring on external layers shall be made fromthe inside surface (Within the hole) of the plated hole to the outer edge of the annular ring on the surface of the board. On the internal layers, the annular ring shall be measured from the edge of the drilled hole to the outer edge of the annular ring.

The annular ring shall be in accordance with the following for the layer(s) indicated. External. The minimum annular ring for an unsupported hole shall be 0.38 mm. The minimum annular ring for a plated through hole shall be 0.13mm.

32


Test Number


1 2 3 4 Internal. The minimum annular ring for internal terminal area on multi layer boards shall be 0.05 mm.

13.1.2.2 Plating Thickness

Inspection for plating thickness (conductor pattern) shall be carried out as specified in clause 13.1.1. Microsection inspection as mentioned in Appendix B with a magnification of 100X, shall be carried out. Plating measurements in the reported as the average of three determinations per each side of the hole. Isolated thick or thin sections shall not be used for averaging. However, isolated areas of reduced Copper thickness shall be measured.

The plating and coating thickness shall conform to the requirement specified herein:- Plating Material: Surface and through hole plating thickness. (see also 13.5) Electroless. Sufficient for subsequent electro deposition. Electrolytic. 0.03 mm (min.). Gold - 0.00125mm (min.) Nickel - 0.005 mm (min.) Tin-Lead - 0.008 mm (min) at the surface as plated. Solder - 0.008 mm (min.) coating at the crest on the surface as coated.

13.1.2.3 Dielectric layer The dielectric layer thickness of the board shall be inspected using an optical apparatus or aid which provides a minimum magnification of approximately 3x.

The minimum dielectric thickness for printed Wiring Boards shall be as defined on the Master Drawing.

13.1.2.4 Under cutting (For external conductors only)

The undercutting at the edge shall be inspected by the method of microsection inspection mentioned in the Appendix 'B'.

Under cutting at each edge of the conductors shall not exceed the total thickness of clad and plated Copper.

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Test Number


1 2 3 4 13.2 Conductor

Pattern (External layers)

(a) The conductor pattern shall be examined using an optical apparatus or aid which pro vides a signification of approximately 3x minimum.

(b) Conductor overhang: - The extent of overhang on conductors plated with gold, shall be determined by measuring the conductor width before and after mechanically removing the overhang metal.

The procedure for removing gold overhang metal, for this test shall be as follows:- Wet the board in tap water at approximately room temperature. While Wet brunch the board with a brass wire brush to remove the overhang metal Brush in the direction of the functional line, using moderate pressure. The microsectioned specimen could also be used alternatively to measure the cross section of the pattern.

(c) Conductor Spacing The conductor spacing shall be inspected using an optical apparatus or aid which provides a minimum magnification of approximately 3x.

The conductor spacing shall be as specified on the Master Drawing.

13.2.1 Conductor Width

The PWBs shall be inspected in accordance with clause 13.1.1

The conductor width and spacing of printed wiring boards shall meet the minimum requirements as specified in the Master Drawing. If nothing is specified, it shall be in accordance with the requirements mentioned in (iii) in clause 13.1.1.2.

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Test Number


1 2 3 4 13.2.2 Circuit Short A test voltage shall be applied

between all common portions of each conductor pattern and all adjacent common portions of each conductor pattern. A minimum voltage 200V in the case of manual testing is applied for 5 seconds. When automatic test equipment is used, the minimum applied test voltage shall be twice the maximum rated voltage on the boards. If maximum rated voltage on the boards, in not specified, in the Master Drawing, the test voltage shall be 40 volt minimum.

The minimum resistance between mutually isolated conductors shall be 2 Megaohms.

13.3 Plating Adhesion

Plating Adhesion shall be tested as follows: - A strip of pressure sensitive cellophane adhesive tape 12.7 mm wide and 50 mm long shall be placed across the surface of the conductor pattern and pressed firmly to the conductor eliminating air bubbles. A tab shall be left for pulling. The tape shall be pulled with a snap pull at an angle of approximately 90 degree to the board. Tape shall be applied to end removed from three different locations on each board tested. Fresh tape shall be used for each test.

There shall be no plating particles or conductor patterns removed from the board except for overhang. If overhang metal breaks off and adheres to the tape, it is an evident of cut growth but not a plating adhesion failure

13.4 Bow and Twist The board shall be placed unrestrained on a flat horizon surface with the convex surface of the panel upward. The maximum vertical

The maximum allowable Bow and Twist shall be 1.5 per cent.

35


Test Number


1 2 3 4 displacement (the vertical distance from the horizontal surface to the maximum height of the determined by taking the measurement and subtracting the thickness of the board if it is included in the height measurement. The vertical displacement divided by the length of the longest side and multiplied by 100 shall be considered the percentage Bow and Twist.

13.5 Plated through hole

Plated through hole examination shall be accomplished by microsectioning using methods given in Appendix 'B'.

Plating thickness shall be as in 13.1.2.2. Plating shall be continuous except for allowable plating voids.

13.5.1 Vertical The microsectioned plated through holes in the vertical plane at the centre of the hole shall be examined for quality of plating at a magnificattion of 50x to 100x. Plating thickness shall be viewed independently. A minimum of the micro section containing atleast three holes shall be prepared for each sample tested. Measurements shall be reported as the average of three determinations per hole. Isolated thick or thin sections shall not be used for averaging.

There shall be no crack, epoxy smear nodule or separation of conductor interface. The plated through hole shall not exhibit more than three plating voides, totaling not more than 5 percent of the wall length.

13.6 Layer to Layer Registration (Applicable only for multiplayer Boards)

Layer to layer registration shall be measured at 100x after vertical microsectioning of two samples as detailed in clause 13.5 and as shown in Fig. 18. One sample shall be vertically cross sectioned parallel to the board length and one vertically cross sectioned perpendicular to the board length. These microsections

Unless otherwise specified, layer to layer conductor pattern misregistrationshall not exceed 0.36 mm.

36


Test Number


1 2 3 4 shall be evaluated by difference of centre lines of all lands of all conductor layers shifted to extreme positions (see fig 1). All lands (external and internal) shall be included in the evaluation of registration. [

13.7 Voltage Proof The Printed Wiring boards shall be tested as follows:- The voltage shall be steadily increased from zero to the proof value at a rate of approximately 500V. (rms or dc) per second. Upon completion of test, the proof voltage shall be gradually reduced to avoid voltage surges. When required suitable current limiting device shall to the value specified. The following details shall apply (a) Magnitude of test voltage 1000V (ac peak or dc) (b) Duration of application 30 seconds for Qualification Approval and 2 seconds for batch acceptance (c) Point of application

(i) Single sided and double sided board. Between two adjoining conductors of the test pattern. (ii) Multilayer board Between all common points of each common portions of each conductor patterns of each adjacent layer.

There shall be no flash over, spark over or breakdown.

37


Test Number


1 2 3 4 13.8 Insulation

Resistance Unless otherwise specified, the insulation resistance shall be measured at 100 Vdc 10 percent. The voltage shall be applied for the period of 1 minute 5 seconds. The points of measurement shall be as follows :-

(a) For Single and double sided boards between two adjoining conductors of the test pattern.

(b) For Multilayer boards between conductor pattern of each layer and the electrically insulated pattern of each adjacent layer.

The insulation resistance shall be 500 Megaohms (Minimum)

13.9 Continuity A current of 1A shall be passed through each conductor or group of interconnected on the terminals at each end of the conductor or group of conductors. The current rating can also be determined from the fig. 19a and 19b. The current shall not exceed than that specified for the smallest conductor in the circuit.

There shall be no open circuit in the specimen The temperature rise shall be not greater than 10 deg C over ambient temperature.

13.10 Solderability The test pattern shall be tested in accordance with JSS 50101 test number 19 procedure 2 big size A, unless otherwise specified but at 260 to 280 deg C.

For Single sided boards the specimens shall exhibit proper wetting of the surface and there shall be no separation or other forms of degradation of the conductive patterns. The wetting of the wall of the plated through hole and the associated land the wetting shall be completed within first two seconds. For double sided (with PTH) and multilayer board, the specimens shall exhibit proper wetting of the wall of the plated through hole and the associated land the wetting shall be completed within first two seconds.

38


Test Number


1 2 3 4 13.11 Pull off strength Three holes per coupon shall be

tested. Insert wires in holes in m a selected terminal area and solder by hand. The wires shall not be clinched. Subject wires to five cycles of unsoldering and soldering by hand after the initial hand soldering. During the five cycles, the wires shall be completely removed during each unsoldering operation and replaced during each soldering operation. A 60W conventional soldering iron with a tip temperature of 232 to 260C (Max) shall be used for the unsoldering and soldering operation. The iron shall be applied to the leads and not to the foil and shall be applied only as long as it is necessary to performs the unsoldering or soldering operation. Following the fifth cycle the printed wiring board shall be clamped to the jaws of bond tester. A pull at the rate of 50.8 mm/minute shall be applied to the wire (on the terminal area side in the case of unsupported hole) The pull shall be applied until the specified load of 22.25 N is reached. The tensile pull shall be calculated using the formula.

The specimens shall with stand a force of 22.25N or tensile pull of 345N/cm whichever is less. A plated shall not be loosened. A conductor or terminal area around an unsupported hole shall not be loosened.

4L --------------------- > or = 345N/cm2 n (d22 d22) Where L = load in N d1 = diameter of the hole d2 = terminal area diameter

39


Test Number


1 2 3 4 The load shall be applied perpendicular to the major surface of the terminal area until the required force is reached of failure occurs. Breaking of a wires pull out shall not be considered as a failure but the wire shall be resoldered and pulled again.

13.12 Temperature cycling (Thermal shock)

As in JSS 50501 test number 20 procedure 1 at the maximum and minimum temperature specified below. The transfer time shall be 5 minutes for single or double sided boards, 2 minutes for single or double sided boards and 2 minutes maximum for multi layer boards. Type Px of JSS 51701 : T65/205 Type GB, GH, GP, GR & GT of JSS 51701 : T65/150 Type GE and GF of JSS 51701 and 51702 : T65/125

13.12.0 Final Measurements

On completion of test, the following measurement shall be made

13.12.1 Visual examination

The boards shall be visually examined

There shall be no blistering measling, crazing or delamination.

13.12.1.2 Continuity As in clause 13.9 As in clause 13.9 13.12.1.3 Bow and twist As in clause 13.4 The maximum Bow and Twist shall

be twice the that of specified in 13.4.

13.13 Climatic The sequence of test shall be carried out in accordance with JSS 50101 at the severities specified. The damp heat severity shall be H12.

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Test Number


1 2 3 4

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13.13.1 Intermediate Measurements

The following tests shall be made subsequent to removal form the conditioning chambers for temperature (dry heat) and temperature (cyclic) tests after allowing the appropriate recovery period specified in JSS 50101.

13.13.1.1 Visual Examination

The board shall be visually examined There shall be no blistering measling, crazing or delamination.

13.13.2 Temperature (Dry Heat)

As in JSS 50101, test number 22, at the temperature specified below:

Type PX of JSS51701 at 105 deg C

Type GB, GH, CP & GT of JSS 51701 at 150 deg C

Type GE and GF of JSS 51701 and 51702 at 125 deg C

13.13.2.1 Continuity As in clause 13.9 As in clause 13.9

13.13.3 Damp Heat (cyclic)

As in JSS 50101 test number 5.

13.13.4 Temperature (Dry cold)

As in JSS 50101 test number 21 at the temperature of (-) 65 deg C

13.13.4.1 Continuity On completion of the test and while the boards are still in the chamber, the resistance and temperature of the test pattern shall be measured and recorded.

As in clause 13.9

13.13.5 Damp Heat (cyclic)

As in JSS 50101, test number 5

13.13.5.1 Insulation resistance

On completion of the final cycle, the boards shall be removed from the chamber. After removing surface moisture, the insulation resistance shall be measured as in clause 13.8 within 5 minutes.

As in clause 13.8

13.13.6 Final The following measurements shall be


Test Number


1 2 3 4 Measurements made at the conclusion of the

sequence.

13.13.6.1 Visual Examination

The boards shall be visually examined.

There shall be no blistering measling, crazing or delamination.

13.13.6.2 Voltage proof

As in clause 13.7 As in clause 13.7

13.13.6.3 Insulation resistance


13.13.6.4 Continuity


13.13.6.5 Bow and Twist As in clause 13.4 The maximum Warp and Twist shall be twice the that of specified in clause 13.4

13.13.6.6 Solderability As in clause 13.10 As in clause 13.10

13.13.6.7 Pull of strength (Bond strength)


13.14 Damp heat (steady state)

As in JSS 50501 test number 7. The damp heat severity shall be H12. During the test, a polarizing voltage of 100 5V dc shall be applied through a current limiting resistor such that the current shall not exceed 1mA.

13.14.1 Final measurements

The following measurements shall be made after the completion of the appropriate recovery period.

13.14.1.1 Visual examination

The boards shall be visually examined

13.14.1.2 Voltage proof As in clause 13.7

As in clause 13.7

13.14.1.3 Insulation Resistance


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Test Number


1 2 3 4 13.14.1.4 Continuity


13.14.1.5 Bow and Twist


13.14.1.6 Solderability


13.14.1.7 Pull off strength (Bond strength)


13.15 Thermal stress The boards shall be conditioned at 121 to 149 deg C for one hour The boards shall than be floated in a solder bath (63/37) tin lead solder composition, maintained at 288C 6 C for a period of 10 seconds then microsectioned and examined in accordance with clause 13.5.

The boards shall exhibit no measling, fractures, separation of plating and conductors, blistering or delamination

13.16 Rework simulation (plated through hole)

The test specimens shall be conditioned at 23 deg C, 40-65% RH for 24 hours, prior to soldering and unsoldering procedure.

Insert the test wires in PTH and solder by machine or hand as applicable. The wire shall have a diameter of 0.5 mm smaller than the hole diameter. The wire shall not be clinched. Subject the wires to five cycles by unsoldering and soldering, by head after the initial soldering. During each cycle the wires shall be completely removed and allowed to cool to ambient temperature and then replaced and resoldered. Apply the iron to the test wire, not to terminal pad and it should be applied only as long as it is necessary to perform the unsoldering and soldering operation. Following the fifth cycle, observe the specimen through microsectioning.

The micro sectioned specimens shall meet the requirements of clause 13.5

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Test Number


1 2 3 4

13.17 Cleanliness A convenient sized funnel shall positioned over an electrolytic beaker. The printed wiring board shall be suspended within the funnel. A wash solution of 75 pr cent by volume of ACS reagent grade isopropyl alcohol and 25 per cent by volume of distilled water shall be prepared, which will have resistivity equal to or greater than 6x10 ohm/centimeters. The wash solution shall be directed in affine stream from a wash bottle on to both Printed Wiring Board until 100 milli-meters of the wash solution is collected for each 254 sq/mm of board surface (including both sides of the board). The time required for the wash activity shall be a minimum of 1 minute. It is imperative that the initial washing be included in the sample to be measured for resistivity. The resistivity of the collected wash solution shall be measured with a conductivity bridge or other instrument of equivalent range and accuracy.

The Printed Wiring Boards shall be within the allowable limits of ionic and other contaminants. If PUBs require permanent ionic within the allowable limiting ionic contaminants prior to the application of solder maskcoating (i.e. the resitivity shall not be less than 2 x 10 ohm cm or equivalent)

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14. SUGGESTION FOR IMPROVEMENT 14.1 Any suggestion for improvement in this document shall be used to: - The Director, Directorate of Standardisation Ministry of Defence H Block New Delhi 110 011.

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APPENDIX 'A'

(Clause 13.1.1)

CONDUCTIVE PATTERN

A.0 Scope :This appendix gives detail requirements of conductive pattern. A.1 Conductor thickness and width: The width and thickness of conductors on the finished printed wiring board shall be determined on the basis of the current carrying capacity required. The temperature rise shall be determined in accordance with fig. 19(a) and 19(b).for the case of manufacture and durability in usage, conductor width and spacing requirements shall be maximized while maintaining the minimum spacing requirements of Table A.1. The minimum Conductor width shown on the master drawing Shall be not less than 0.10mm.To maintain the conductor width shown on the master drawing the line width on the production master shall be compensated for process allowance Table A.4 of the Appendix A. A.2 Conductor with less than 90 deg. included angle: All conductors that change direction Where the included angle is lese than 90 deg. shall have external corners of the conductor rounded. A.3 Conductors: The length of a conductor between any two lands should be held to a minimum. However, conductors which are straight lines and run in X, Y or 45deg directions in general are preferred to aid computerized documentation for mechanized or automated layouts. A.4 Conductor Spacing: large spacing shall be used whenever possible and the minimum spacing between conductors, between conductor patterns, and between conductive materials (such as conductive marking s or mounting hardware) and conductors shall be in accordance with Table A.1. and defined on the master drawing. To maintain the conductor spacing shown on the master drawing, space width on the production master shall be compensated for process allowance as shown on Table A.4 of the Appendix. Plated-through holes passing through internal foil planes (ground and voltage and thermal planes shall meet the same minimum clearance between the plated-through hole and foil of ground planes as required for spacing between internal conductors. A.5 Edge Spacing: The minimum spacing between conductive patterns and the edge of the printed wiring board or any adjacent conductive surface, such as supporting structure or frames (nonmoving), shall be not less than the minimum spacing specified in Table A.1 plur 0.38 mm, provided the edges are protected from the physical harm in the installed assembly configuration. Printed wiring not so protected shall have a minimum

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conductor to edge distance of 1.25 mm. The edge spacing requirement is not applicable to heat sinks and ground planes. To maintain the edge spacing shown on the master drawing, the edge spacing shall be compensated for process allowances shown in Table A.4.

TABLE A.1: CONDUCTOR SPACING

Minimum spacing Voltage between conductors DC or AC peak (volts)

Surface layers Internal layers

0-100 0.13 mm 0.10 mm 101-300 0.38 mm 0.20 mm 301-500 0.76 mm 0.2525 mm Greater than 500 1/

0.00305 mm (per volt)

0.0025 mm (per volt)

1/ for reference only, voltages greaer than 500 v should be evaluated for the specific design application. A.8 Large internal conductive areas (for multilayer boards only): When a conductive area that extends beyond 25.4 mm diameter circle is used on an internal layer, the layer should be placed areas that will breakup large conductive area but retain the continuity and functionality of the conductor. If more than one internal layer has a large conductive area, the layers should be located in the board to provide balanced construction. A.9 Interfacial connections: Interfacial connections on double sided and multilayer printed wiring boards shall be made by use of plated-through holes only. Wires, standiff terminals, eyelets, rivets, or pins shall not be used to provide interfacial connections. A.10 Solder fillets and plugs: Printed wiring boards subjected to wave or dip solderings shall be designed to facilitate flow of solder around components leads in plated through holes and into plated-through holes without leads, so as to create a solder plug. Careful consideration shall be given to hole-to-lead diameter clearance, hole to board thickness rations and heat relief of metal planes to promote solder plugging. In the event solder plugging due to natural capillary action is not possible, such as when a heat sink is bonded directly over plated-through holes, the design shall include provision for prevention of solder, flux or other chemical from entering the plated-through holes. Solder may be prevented from entering the holes by profiling these holes with an appropriate polymer plug, covering the holes with a sheet of permanent bonded material, tenting the holes with a permanent solder mask of blocking these holes with some

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JSS 52300: 1992 (Revision No. 1) Reaffirmed 2003 temporary techniques that will prevent solder access to the hole. All techniques must have sufficient durability not to break up when exposed to the solder process. The printed wiring assembly shall define the absence of such solder plug requirements. As a minimum, solder plugs shall be required in: (i) All electrically functional and non -functional plated through hole with a

lead is required to be surrounded 360 deg c by the

JSSStandards JSS 52300 1992

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