EEWeb Pulse - Issue 7, 2011

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    PULSE

    EEWeb.c

    Issu

    August 16, 20

    Sam WurzelOctopart

    Electrical Engineering Commun

    EEWeb

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    TABLE OF C ONTENTS

    Sam Wurzel 4CO-FOUNDER AND CEO, OCTOPART INC.Interview with Sam Wurzel, internet industry entrepreneur.

    The Righthand Side of the Weave Effect

    InequalityBY MIKE STEINBERGER WITH SISOFT

    Introduction to Touchscreens 11BY STEVE KOLOKOWSKY AND TREVOR DAVIS WITH CYPRESS

    RTZ - Return to Zero Comic 16

    How to properly manage differential skew on PC board traces due to local variations in board

    material.

    Kolokowsky and Davis provide an introduction to touchscreens and the components that make

    them possible.

    7

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    INTERVIEW

    Sam WurzelOctopart

    Sum up Octopart in one

    sentence.

    Octopart solves the problem ofelectronic part search on the web

    - we provide distributor stock and

    pricing information, datasheets,

    and advanced search features with

    a focus on speed and simplicity.

    What is your value

    proposition?

    Choosing and sourcing parts is

    hard and time consuming. Octopart

    exists to solve that problem - its the

    easiest and fastest way to find parts

    online.

    Can you tell us about the early

    start-up days at Octopart?

    The early days were a lot of fun! In

    the summer of 2006, Andres and I

    were still in physics grad school.

    Andres was in Berkeley and I was

    in Boulder. Every day wed come

    home from the lab and log into a

    linux box in my living room to work

    on Octopart. At that point we didnt

    know anything about databases or

    web technologies so most of what

    we did was learn.

    By early 2007 we had both quit

    grad school and I had moved out

    to Berkeley to work on Octopart

    full time. For a while I was living

    on Andres couch and we wouldliterally wake up, work on Octopart

    all day and night and then fall

    asleep. We had about 5 computers

    stacked in Andres room and we

    were running the site from his cable

    modem connection. I remember the

    first time we saw a search come in

    that we couldnt directly trace to one

    of us or our friends - I think it came

    from Turkey. To this day still I dont

    know how they found us.

    Has the direction or vision of

    Octopart changed from your

    initial vision of the service?

    Not really. From the beginning the

    plan was to fix part search and

    thats still the goal. The design

    of the site and the access model

    has not changed either. From the

    beginning we wanted a clean

    layout and we wanted everyone

    to have access to complete

    part information without anycumbersome registration process.

    One of the frustrations we had with

    existing sites was that they were

    filled with distracting ads and they

    required you to register or pay for

    the service.

    What has been the biggest

    technical challenge in

    developing Octopart?

    The quantity of data we are dealing

    with is very large and it changes

    often. There are 15 million parts

    in the database and we have to

    keep all the pricing and availability

    numbers are up to date. We also

    have to make sure the data is

    accurate which, given the scale of

    the data, is challenging.

    Also, the search aspect is technically

    challenging. Maintaining full textand parametric search capability

    over 15 million parts is tough.

    Especially when there are many

    different types of parts, each with

    their own attributes.

    Sam Wurzel, Andres Morey, and Harish Agarwal, Co-Founders of Octopart

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    INTERVIEW

    What has been the toughest

    non-technical challenge you

    have dealt with or are dealing

    with?

    Establishing ourselves in theindustry and communicating who

    we are and what were trying to do

    has been challenging. When we

    started Octopart we did not have a

    single contact within the electronics

    industry. We just kind of jumped

    into it. Weve made a lot of progress

    on that front but theres still a lot of

    work to do.

    How do you entice users toOctopart?

    We believe that if people find

    Octopart useful they will tell their

    friends and colleagues about it.

    Our entire development process is

    based around doing whats best for

    users.

    How do you differentiate

    yourselves from other

    competing search engines?

    We take the approach of building

    a full part database by combining

    data from lots of different sources.

    This gives us a few advantages over

    other part search engines:

    1. You get a full view of a single

    part. You can see all of the

    distributors of that part, all of

    the images, all of the datasheetsand a complete set of part

    attributes.

    2. You can search by category

    or do parametric search if

    you dont know the exact part

    number youre looking for.

    3. We provide an API, http://

    octopart.com/api which allows

    anyone to develop applications

    which leverage all of this part

    information.

    Octopart solvesthe problem ofelectronic partsearch on the

    web - we providedistributor stock

    and pricinginformation,

    datasheets, andadvanced searchfeatures with afocus on speed

    and simplicity.

    Do you plan on integrating

    social media into Octopart?

    Sure, we already allow users to

    leave comments about parts and

    were thinking of other ways to

    integrate social media in ways that

    make sense. Getting help from

    other engineers is one of the best ways to solve problems so were

    thinking about ways to facilitate that

    on Octopart.

    Where do you see Octopart in

    the next fve years?

    I see Octopart as the repository for

    all part data on the web. By making

    that data available via API well open

    the door to lots of new applications,

    most of which we havent even

    anticipated.

    http://octopart.com/apihttp://octopart.com/apihttp://octopart.com/apihttp://octopart.com/apihttp://bit.ly/jpn9V5
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    The RighthandSide of theWeave Effect

    Inequality

    Mike SteinbergerLead Architect

    Serial Channel Products

    What Inequality?

    Over the last several years, a lot has been written about

    the introduction of differential skew into PC board tracesdue to local variations in the dielectric constant of the

    board material. (For a small sampling, see [1], [2], [3],

    [4]) These local variations are due to variations in the

    percentage of glass cloth in the laminate, and can have

    a measurable effect when the traces in a differential pair

    run parallel to the fibers in the glass cloth. Hence the

    term weave effect.

    While several papers derive a maximum trace length as

    a function of data rate, there is very little discussion of

    the performance requirements those calculations were

    based on, or the way those performance requirements

    were derived.

    As skilled and disciplined engineers, we write a

    tolerance equation such as:

    costs. Choosing that righthand value is an important part

    of our job, so we should consider carefully how we makethat choice.

    This is the inequality referred to in the title of this article,

    and the purpose of this article is to offer some insight

    into choosing a value for tmax, the righthand side of this

    inequality.

    Skew Modeling

    For this study, the transmission model is shown in Figure

    1.

    For a 5 Gb/s transmission path, a 30 length of differentialFR4 trace was broken into ten segments, with the

    differential skew inserted uniformly between these

    segments. This model was chosen because it models

    the distributed nature of the skew due to weave effect.

    The conclusions of this study are insensitive with respect

    to modeling approach, however. Lumping the differential

    skew into a single transmission line at the end of the

    transmission path produces essentially the same link

    performance.

    t t< maxskew t t tskew true complement / -and we choose a value for the righthand side that will

    result in acceptable product yield while minimizing

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    TECHNICAL ARTICLE

    Figure 2 shows the eye height for the optimized solution

    as a function of differential skew for seven different

    combinations of equalizers. The transmit de-emphasis

    consisted of four taps, including one pre-cursor tap, the

    linear equalizer varied a single zero while keeping the

    peak gain constant, and the DFE had five taps.

    These results were generated using a performance

    criterion which is a combination of eye width and eye

    height; so one should not attempt to compare and contrast

    the results from different combinations of equalizers

    based solely on eye height. Also, the results will vary with

    different linear equalizer designs or different numbers of

    transmit or receive taps. The data in Figure 2 is valuable

    in that it shows the effect of differential skew on a number

    of different choices of equalizer. In particular, its clear

    that when the differential skew becomes greater thana half a bit time (0.5 UI), bad things start to happen

    regardless of which combination of equalizers is chosen.

    Below a skew of 0.5UI, some combinations of equalizers

    appear to be better able to compensate for the effects

    of differential skew than others. Thus, the amount of

    differential skew that can be tolerated is a function of

    the equalization chosen as well as the performance

    requirements of the channel.

    The Case of the Creeping Suck-out

    One can understand why 0.5UI differential skew is such afundamental limit by examining the unequalized transfer

    functions. Figure 3 compares the transfer function for

    0.44UI of differential skew to the transfer function for

    0.61UI of differential skew. While both transfer functions

    have a pronounced dip (i.e., suck-out) in them, the dip

    for 0.44UI is centered more or less around the data rate

    while the dip for 0.61UI is clearly below the data rate.

    Effect of Equalization

    In SiSofts Quantum Channel Designer, we have a

    feature which optimizes the combined transmit and

    receive equalization during the statistical analysis phase

    of the simulation. The transmit de-emphasis, receiver

    linear equalizer, and DFE can each be independently

    included or excluded from the equalization solution,

    resulting in a total of eight possible combinations of

    equalizers. For a given channel configuration (e.g.,

    differential skew) and combination of equalizers,the optimal performance is calculated in a couple of

    seconds as part of the statistical analysis. This makes it

    convenient to evaluate the optimal performance under a

    wide range of conditions.

    Differential Skew (UI)

    EyeHe

    ight(V)

    0

    0.25

    0.2

    0.15

    0.1

    0.05

    0

    0.2

    PK+DFE

    0.4 0.6 0.8 1.0

    TX+PK+DFE

    PK

    TX+PK

    DFE

    TX+DFE

    TX

    Figure 2: Eye height vs. differential skew vs. optimized equalizer

    configuration

    Hertz (GHz)

    DB

    0

    0.0

    -10.0-20.0

    -30.0

    -40.0

    -50.0

    -60.0

    -70.01.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0

    Transfer FunctionUnequalized BLUE: 0.44UI skew RED: 0.61UI skew

    Figure 3: Unequalized transfer function for 0.44UI and 0.61UI

    differential skew

    A I

    A I

    TX1sisoft_serdes

    SiSoft_TX

    W1 W2 W3 W4

    W5 W6 W7 W8

    W9 W10 W11 W12

    W13 W14 W15 W16

    W17 W18 W19 W20

    RX1SiSoft_RX

    Figure 1: Circuit model for differential skew

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    TECHNICAL ARTICLE

    As the differential skew is increased, the location of the

    dip moves even lower in frequency. The approximate

    equation is:

    criterion. While these choices may be appropriate for

    some designs, many designs will come in at a much

    lower cost if one explicitly calculates the performance

    margin and accepts a slightly reduced yield due to

    extremes in differential skew.

    References

    [1] Jeff Loyer, Richard Kunze, and Xiaoning Ye, Fiber

    Weave Effect: Practical Impact Analysis and Mitigation

    Strategies, paper 6-TA2, DesignCon2007.

    [2] Scott McMorrow and Chris Heard, The Impact of

    PCB Laminate Weave on the Electrical Performance of

    Differential Signaling at Multi-Gigabit Data Rates, paper

    6-TA3, DesignCon2005.

    [3] Christopher White, Andrew Becker and Jim Fitzke,

    Skew Impact Estimation on High Speed Serial

    Channels Using Mathematical Analysis and Accurate

    Lab Measurements, paper 7-WA2, DesignCon2010.

    [4] Russell Dudek, John Kuhn and Patricia Goldman,

    Opening Eyes on Fiber Weave and CAF, Printed Circuit

    Design & Fab, http://pcdandf.com/cms/component/

    content/article/ 220-2009-issues/6025-opening-eyes-on-

    fiber-weave-and-caf, 01 April 2009.

    About the Author

    Michael Steinberger, PhD, has over 30 years experience

    in the design and analysis of very high-speed electronic

    circuits. Dr. Steinberger began his career at Hughes

    Aircraft, designing microwave circuits. He then moved

    to Bell Labs, where he designed microwave systems that

    helped AT&T move from analog to digital long-distance

    transmission. He was instrumental in the development of

    high-speed digital backplanes used throughout Lucents

    transmission product line. Prior to joining SiSoft, Dr.

    Steinberger led a group of over 20 design engineers

    at Cray, Inc. responsible for SerDes design, high-

    speed channel analysis, PCB design, and custom RAM

    design.

    Figure 4 shows how well the various combinations of

    equalizer cope with the two values of differential skew.

    From Figure 4, its clear that while most of the

    combinations of equalizer can cope fairly readily with a

    dip at or above the data rate, they have a much harder

    time coping with a dip thats below the data rate. They

    DB

    0

    0.0

    -10.0

    -20.0

    -30.0

    -40.0

    -50.0

    -60.0

    -70.0

    -80.0

    1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0

    Transfer FunctionUnequalized BLUE: 0.44UI skew RED: 0.61UI skew

    Figure 4: Equalized transfer functions for 0.44UI and 0.61UI of

    differential skew

    have at best a limited ability to increase the gain in thefrequency range where the dip occurs.

    Choosing tmax

    From Figure 2, its clear that the choice of the maximum

    differential skew is going to be a function of the

    equalization solution as well as the performance

    requirements for the channel. The allowable differential

    skew can go as high as 0.5UI, but accepting any value

    higher than that is a bad idea.

    A couple of concluding thoughts:

    A linear receive equalizer that has its gain peak above

    half the data rate will tend to be a little more effective at

    equalizing differential skew because it will be able to

    increase the gain in the frequency range where a dip

    could occur.

    A lot of the published results only state acceptable

    trace lengths for a very pessimistic choice of material

    properties and a conservative choice of performance

    f t2

    1

    dip skew

    .

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    INTRODUCTION TO

    TechnologyOptions in aTouch-based World

    TOUCHSCREENS

    Ray SalemiVerification Consultant

    Steve KolokowskySr Member of the Technical Staff

    Trevor DavisDirector of Marketing & Applications

    Every local mobile phone retailer, every electronics

    store, and most every consumer electronics

    company in the world is selling touchscreensand all of

    them claim to be experts and to have the most advanced

    or desirable technology. But do they? In fact, how is a

    designer, engineer, or consumer even able to tell which

    technology is right for their product development? What

    are the key technologies even available in the market

    and what is the benefit of one over another? How will

    one technology last versus another in everyday use?

    While it is true that there are many different touchscreen

    technologies in the world, it is also true that the market

    and application demands of different product segments

    do demand different technology choices. Understanding

    the benefits and limitations of current technologies will

    help the consumer to make the most appropriate choice

    in technology.

    Touchscreen Components Revealed

    While there are many different types of touchscreen

    products, there is a relatively consistent set of

    components that make a touchscreen product possible.

    Whether the developer is making a new touchscreen-

    enabled phone, Global Positioning System (GPS), touch-

    enabled medical device, or virtually any other touch

    product, there are five basic components to the system:

    Figure 1: Touchscreen System Components

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    TECHNICAL ARTICLE

    Coverlens or Bezel

    The coverlens bezel is the outward facing component

    of the product. This is how the consumer interacts with

    the product. In some products, this coverlens could

    simply be a protective cover to prevent scratching and

    damage, or it can actually be part of the touch sensing

    system. In other technology systems it can actually hide

    small cameras or infrared sensors that detect a persons

    touch. Either way, much of the consumers perception

    of the products look and feel will be determined by the

    materials chosen for the coverlens.

    Touch Controller

    Once contact is initiated with a product, the electronics

    in the system are activated for action. In todays

    systems, the touch-controller is a small microcontroller-

    based chip like the Cypress TrueTouch that is placedbetween the touch sensor and systems host controller.

    This chip can either be located on a controller board

    inside the system or it can be located on a flexible

    printed circuit (FPC) affixed to the glass touch sensor.

    This touch-controller takes information from the touch

    sensor and translates it into information the systems

    host controller can understand.

    Touch Sensor

    A touchscreen sensor is a clear glass or acrylic panel

    with a touch responsive surface. This sensor is placedover a graphic display so that the touch area of the

    panel covers the viewable area of the screen. There are

    many different touch sensor technologies on the market

    today, each using a different method to detect touch

    input. Basic operation, however, remains the same as

    these technologies all use an electrical current running

    through the panel that, when touched, causes a voltage

    or signal change. This voltage change is sensed by the

    touch controller to determine the location of the touch on

    the screen.

    Display

    Most touchscreen systems work on top of an Liquid

    Crystal Display (LCD) or the newer Active Matrix

    Organic Light Emitting Diode technology (AMOLED).

    Displays for a touch-enabled product should be chosen

    for the same reasons they would in a traditional system:

    resolution, clarity, refresh speed, cost. One major

    consideration for a touchscreen, however, is the level of

    electrical emission. Because the technology in the touch

    sensor is based on small electrical changes when the

    panel is touched, an LCD that emits a lot of electricalnoise can be difficult to design around.

    System Software

    Without system software understanding of how to

    interpret a touch signal, touch system hardware is

    useless. The system software allows the touchscreen and

    system controller to work together. Apples iOS exposed

    gestures to everyone, providing zoom, swipe, and

    rotate in many applications. Windows 7 has integrated

    multi touch gestures into the core operating system and

    Internet Explorer in several interesting ways. The shake

    gesture minimizes all windows other than the active one.

    Two finger tap is a quick zoom to allow selection of small

    icons. Android provides developers with a very flexible

    framework to define their own gestures, which will drive

    more gesture innovation in the mobile device market.

    Figure 2: Four Primary Touchscreen Technologies

    1. Surface Capacitance 2. Infrared Touchscreen 3. Resistive Touch 4. Capacitive Touch

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    TECHNICAL ARTICLE

    Primary Touchscreen Technology Options

    Resistive Touchscreens

    Resistive touchscreens remain the most common

    touchscreen technology. They are used in high-traffic

    applications and they are immune to water or other

    debris on the screen. Resistive touch screens are

    usually the lowest cost touchscreen solution. Because

    they react to pressure, they can be activated by a finger,

    gloved hand, stylus or other object like a credit card

    or fingernail. The Nintendo DS uses a 4-wire resistive

    touchscreen that can be use with a plastic stylus.

    Surface Capacitive Touchsreens

    Surface Capacitive technology works with a glass or

    plastic cover lens up to several millimeters thick. This

    provides a clearer and more durable display thanthe flexible plastic cover typically used in a resistive

    touchscreen. In a surface capacitive display, sensors

    in the four corners of the display detect capacitance

    changes due to touch. These touchscreens can only

    be activated by a finger or other conductive object.

    Touchscreen slot machines and poker machines are

    two main applications for these screens. The main

    disadvantage of surface cap screens is accuracy.

    Typical position error is 1-1.5% of screen size, which is

    plenty for selecting a card or starting a slot machine.

    Infrared or Camera-based Touchscreen

    IR touchscreen technology does not require any

    changes to the display stackup, since it works in front

    of the screen. This makes it ideal for vandal-resistant

    applications. While surface capacitance systems

    observe disruption in electrical signals, IR touchscreens

    observe disruption in IR signals that cross the plane of

    the display. IR systems are used almost exclusively on

    kiosk or large form factor displays because of their bulky

    profile and large power requirement. A touch signal

    can be detected from almost any object that disrupts

    the IR beam which makes IR technology more ideal forglove or passive stylus use (though accuracy for stylus

    is quite low). The Microsoft Surface interface uses IR

    cameras to detect multiple touches without projecting

    IR beams above the touch surface.

    Projected Capacitive Touchscreens

    Projected capacitive touchscreens are the latest entry to

    the market. This technology also offers superior optical

    clarity, but it has significant advantages over surface

    capacitive screens. Projected capacitive sensors require

    no positional calibration and provide much higher

    positional accuracy. Projected capacitive touchscreens

    are also very exciting because they can detect multiple

    touches simultaneously. Apples iPod Touch and iPhone

    use this type of touchscreen.

    Touchscreen Technology Revealed

    The most widely used touchscreen technologies in

    consumer electronics today are resistive and capacitive.

    As these are the two most common, we will focus further

    technology discussion here. In fact, most people have

    interacted with resistive touchscreens while using an

    ATM at the bank, or at the credit card checkout in most

    stores. Projective capacitance touchscreens, on the

    other hand, are most known for their use in the mobilehandset application. Both resistive and capacitive

    technologies have a strong electrical component, both

    use ITO (Indium-Tin-Oxide, a clear conductor) as their

    primary technology component, and both are used in

    high volume all over the world.

    A resistive touchscreen consists of a flexible top layer,

    then a layer of ITO (Indium-Tin-Oxide), an air gap, and

    then another layer of ITO. The panel typically has either

    four, five, or eight wires attached to the ITO layers: one

    on the left and right sides of the X layer, and one on the

    top and bottom sides of the Y layer

    A touch is detected when the flexible top layer is pressed

    down to contact the lower layer. The location of a touch

    is measured in two steps: First, the X right is driven to

    a known voltage, and the X left is driven to ground and

    the voltage is read from a Y sensor. This provides the X

    coordinate. This process is repeated for the other axis to

    determine the exact finger position.

    Resistive touchscreens also come in 5-wire, and 8-wire

    versions. The 5-wire version replaces the top ITO layer

    with a low-resistance conductive layer that provides

    better durability. The 8-wire panel was developed to

    enable higher resolution by enabling better calibration of

    the panels characteristics.

    Some of the benefits of resistive technology are that they

    can easily be used for larger size displays (10 inches +)

    and can be used to detect the touch of any non-conductive

    pressure. This makes resistive touchscreens the current

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    TECHNICAL ARTICLE

    default for products that need the use of stylus pen input.

    There are, however, several drawbacks to resistive

    technology. The flexible top layer scratches easily, has

    only 75-80 percent clarity, and the resistive touchscreen

    measurement process has several error sources. If

    the ITO layers are not uniform, the resistance will not

    vary linearly across the sensor. Measuring voltage

    to 10 or 12-bit precision is required, which is difficult

    in many environments. Many of the existing resistive

    touchscreens require periodic calibration to realign the

    touch points with the underlying LCD image.

    Conversely, projected capacitive touchscreens have no

    moving parts. The only thing between the LCD and the

    user is ITO and glass, which have nearly 100 percent

    optical clarity. The projected capacitance sensing

    hardware consists of a glass or acrylic top layer,

    Figure 3: Resistive Sensing Circuit

    Figure 4: Capacitive Sensing Circuit

    followed by an array of X and Y sensors that are either

    deposited or etched in an ITO layer in either a single

    layer (lowest cost) or in separate layers depending on

    the manufacturers process. The panel will have a wire

    for each X and Y sensor, so a 10 x 14 panel will have 24

    connections, while a 12 x 20 panel will have 32 sensor

    connections.

    As a finger or other conductive object approaches the

    screen, it creates a capacitor between the sensors and thefinger. This capacitor is small relative to the others in the

    system (about .5pF out of 20pF), but it is measurable by

    several techniques that typically involve rapidly charging

    an in-circuit capacitor and measuring the discharge time

    through a resistor. Two sensing types are commonly

    used, mutual capacitive and self-capacitive sensing. Self

    cap senses the increase in self-capacitance of a sensor

    as a finger touches the screen. Mutual cap measures

    the decrease in capacitive coupling between a transmit

    sensor and a receive sensor as shown in Figure 3 and 4.

    A projected capacitive sensor array is designed so that

    a finger will interact with more than one X sensor and

    more than one Y sensor at a time. This enables software

    to accurately determine finger position to a very fine

    degree through interpolation. Since projected capacitive

    panels have multiple sensors, they can detect multiple

    fingers simultaneously, which is impossible with other

    technologies. This enables exciting new applications

    based on multiple finger presses.

    Because capacitive sensing based solutions do not

    sense through pressure, they are much more durablethan resistive technology. They also can be based on a

    much harder cover lens material which is very pleasing

    to the touch which gives the user an enjoyable touch

    experience. And because there are fewer layers of

    material than a resistive panel, and the etched ITO of a

    capacitive sensor is colorless, capacitive touch solutions

    have much better transmissivity and have a much sharper

    visual image.

    So, despite the fact that touch sensors are shipped in

    many different product categories and product types,

    their basic construction is quite similar from product toproduct. The underlying technology, however, can be quite

    different and can deliver very different user experiences.

    Depending on the end product requirement, a designer

    may choose to use one technology choice over another. If

    large screen form factor is required, perhaps IR sensing

    is ideal. For low cost, stylus Point of Sale terminals where

    a pen input is critical, a resistive screen might be best.

    For a wall mounted customer information kiosk, surface

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    TECHNICAL ARTICLE

    capacitive touchscreens might be a good choice. And

    for ultra portable handsets or mobile devices with

    multi-touch input, projected capacitance might be

    the best option. In the end, it is the user experience

    and product requirements that dictate the technology

    choice for touchand now you know your options.

    About the Authors

    Steve Kolokowsky is currently working on

    touchscreen solutions for Cypress Semiconductor. He

    has over 20 years of experience creating embedded

    solutions and software. Steve has been involved with

    Cypress TrueTouch solutions and USB solutions

    including Cypress best-selling USB mass storage

    chip, the AT2LP. Prior to Cypress, Steve worked for

    Cirrus Logic creating DSP tools and development kits.

    Steve has written over 40 technical articles that have

    been published in at least six languages. He has over 10

    patents issued and several more applications pending.

    Trevor Davis is currently the Director of Marketing

    & Applications for Cypresss Consumer andComputation Division (CCD) focused on User

    Interface in consumer products. Trevor received his

    undergraduate degree from the United States Air Force

    Academy and also holds his Masters in Business

    Administration. Trevor has worked in high technology

    positions for the military, nonprofit, and commercial

    sectors for the past 15 years and is fascinated by the

    speed of innovation in User Interface products.

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