Bistable Multivibrator

26

Circuit Simulation and Synthesis

Project Report

Submitted To: -Submitted By:-Mr. Arun Kumar Chatterjee Ravneet Singh101386013(G2)E.C.E.- 7

IndexSr. No.ContentPage No.

1.Introduction to 555 timer IC4-6

2.Introduction to Voltage Regulator7

3.Circuit Diagrams8-9

4.Waveforms10-11

5.SPICE Netlist12-26

Acknowledgement

I take this opportunity to express my profound gratitude and deep regards to my guide Mr. Arun Kumar Chatterjee for his exemplary guidance, monitoring and constant encouragement throughout the summer training. The blessing, help and guidance given by him time to time shall carry me a long way in the journey of life on which I am about to embark. I am obliged to staff members of this 6 weeks summer training, for the valuable information provided by them in their respective fields. I am grateful for their cooperation during the period of my training. Lastly, I thank almighty, my parents and friends for their constant encouragement without which this project would not be possible.

Introduction to 555 Timer

The 555 timer circuit is a popular IC that can be used to implement astable and monostable multivibrator circuits as well as other circuits. The 555 is a linear IC (like an operational amplifier or a voltage regulator) rather than a digital IC, thus it does not necessarily use TTL voltage levels. In fact, the supply voltage for the 555 can range from 4.5V to 18V. If a 5V supply if used, it can easily interface with TTL circuits.

Pin Diagram of 555 Timer IC:-

Working of Different Pins:-

1. Pin 1:Grounded Terminal:All the voltages are measured with respect to the Ground terminal.2. Pin 2: Trigger Terminal:The trigger pin is used to feed the trigger input hen the 555 IC is set up as a monostable multivibrator. This pin is an inverting input of acomparatorand is responsible for the transition offlip-flopfrom set to reset. The output of the timer depends on the amplitude of the external trigger pulse applied to this pin. A negative pulse with a dc level greater than Vcc/3 is applied to this terminal. In the negative edge, as the trigger passes through Vcc/3, the output of the lower comparator becomes high and the complimentary of Q becomes zero. Thus the 555 IC output gets a high voltage, and thus a quasi-stable state.3. Pin 3:Output Terminal:Output of the timer is available at this pin. There are two ways in which a load can be connected to the output terminal. One way is to connect between output pin (pin 3) and ground pin (pin 1) or between pin 3 and supply pin (pin 8). The load connected between output and ground supply pin is called thenormally on loadand that connected between output and ground pin is called thenormally off load.4. Pin 4:Reset Terminal:Whenever the timer IC is to be reset or disabled, a negative pulse is applied to pin 4, and thus is named as reset terminal. The output is reset irrespective of the input condition. When this pin is not to be used for reset purpose, it should be connected to + VCCto avoid any possibility of false triggering.5. Pin 5:Control Voltage Terminal:The threshold and trigger levels are controlled using this pin. The pulse width of the output waveform is determined by connecting a POT or bringing in an external voltage to this pin. The external voltage applied to this pin can also be used to modulate the output waveform. Thus, the amount of voltage applied in this terminal will decide when the comparator is to be switched, and thus changes the pulse width of the output. When this pin is not used, it should be bypassed to ground through a 0.01 micro Farad to avoid any noise problem.6. Pin 6:Threshold Terminal:This is the non-inverting input terminal of comparator 1, which compares the voltage applied to the terminal with a reference voltage of 2/3 VCC. The amplitude of voltage applied to this terminal is responsible for the set state of flip-flop. When the voltage applied in this terminal is greater than 2/3Vcc, the upper comparator switches to +Vsat and the output gets reset.7. Pin 7:Discharge Terminal:This pin is connected internally to the collector of transistor and mostly a capacitor is connected between this terminal and ground. It is called discharge terminal because when transistor saturates, capacitor discharges through the transistor. When the transistor is cut-off, the capacitor charges at a rate determined by the external resistor and capacitor.8. Pin 8:Supply Terminal:A supply voltage of + 5 V to + 18 V is applied to this terminal with respect to ground (pin 1).Block Diagram of 555 Timer:-

The block diagram of a555 timeris shown in the above figure. A 555 timer has two comparators, which are basically 2 op-amps), an R-S flip-flop, two transistors and a resistive network. Resistive network consists of three equal resistors and acts as a voltage divider. Comparator 1 compares threshold voltage with a reference voltage + 2/3VCCvolts. Comparator 2 compares the trigger voltage with a reference voltage + 1/3 VCCvolts.Output of both the comparators is supplied to the flip-flop. Flip-flop assumes its state according to the output of the two comparators. One of the two transistors is a discharge transistor of which collector is connected to pin7. This transistor saturates or cuts-off according to the output state of the flip-flop. The saturated transistor provides a discharge path to a capacitor connected externally. Base of another transistor is connected to a reset terminal. A pulse applied to this terminal resets the whole timer irrespective of any input.

Introduction to Voltage Regulator

7805is avoltage regulatorintegrated circuit. It is a member of 78xx series of fixed linear voltage regulator ICs. The voltage source in a circuit may have fluctuations and would not give the fixed voltage output. Thevoltage regulator ICmaintains the output voltage at a constant value. The xx in 78xx indicates the fixed output voltage it is designed to provide. 7805 provides +5V regulated power supply. Capacitors of suitable values can be connected at input and output pins depending upon the respective voltage levels.

Pin Diagram Of voltage Regulator 7805:-

Working of different Pins:-

1. Pin 1(Input Pin): The Input pin is the pin that accepts the incoming DC voltage, which the voltage regulator will eventually regulate down to 5 volts.2. Pin 2(Ground): Ground pin establishes the ground for the regulator.3. Pin 3(Output Pin): The Output pin is the regulated 5 volts DC.

Bistable Multivibrator using 555 Timer ICAim: - Design a Bistable Multivibrator using 555 timer IC. For supply voltage use a Full Wave Bridge Rectifier using 78XX series voltage regulator.Working: - In Bistable mode, the 555 timer acts as a basic flip-flop. The trigger and reset inputs (pins 2 and 4 respectively on a 555) are held high viaPull-up resistorswhile the threshold input (pin 6) is simply floating. Thus configured, pulling the trigger momentarily to ground acts as a 'set' and transitions the output pin (pin 3) to Vcc (high state). Pulling the reset input to ground acts as a 'reset' and transitions the output pin to ground (low state). No timing capacitors are required in a Biastable configuration. Pin 5 (control voltage) is connected to ground via a small-value capacitor (usually 0.01 to 0.1 uF); pin 7 (discharge) is left floating.

Circuit Diagram:- Power Supply:-

Bistable Multivibrator Circuit:-

Bistable Multivibrator Circuit (With Power Supply):-

Waveforms:-

Power Supply:-

Bistable Multivibrator:-

Power Supply and Bistable Multivibrator:-

SPICE Netlist:-

** Design2 *** * NI Multisim to SPICE Netlist Export* Generated by: RAVNEET* Tue, Jul 22, 2014 09:39:52 *

*## Multisim Component V1 ##*vV1 12 13 dc 0 ac 1 0+ distof1 0 0+ distof2 0 0+ sin(0 {220*1.414213562} 50 0 0 0)

*## Multisim Component S2 ##** !!!BEGIN-INTERACT* 2.0 constant high* 0.0 constant low* 2 constant max_states* low VARIABLE volt** :MAP_KEYBOARD_INPUT ++++K1 1 ++++k1 -1 ;** : UPDATE_SETTINGS* *animation_state max_states low high STATE volt * GRADUAL_CHANGE_AT_RUN * ;** :KEYBOARD_INPUT locals| shift_state |* shift_state *animation_state max_states NEXT_STATE_WRAP* ==>_*animation_state* UPDATE_SETTINGS* ;** :GRADUAL_CHANGE_AT_RUN locals| ref value |* value SET_INSTANCE Vsource ::V V2 dc* ;** : INIT_IMOUSE_OPTION* 1 0 4 IMOUSE_SET* ;** : GET_IMOUSE_SUBCOMPS ( -- [iIdxN ... iIdx1] )* 1* ;** : ON_SUBCOMP_IMOUSE_EVENT locals| eEventType nOptions iSubCompIdx |* eEventType 2 = if* -1* -1 KEYBOARD_INPUT* else* 0* endif* ;** ( Initialize the settings )* UPDATE_SETTINGS* INIT_IMOUSE_OPTION** :BEGIN_PLOT* UPDATE_SETTINGS* ;** :BEGIN_ANALYSIS* UPDATE_SETTINGS* ;** !!!END-INTERACT

xS2 9 0 SwitchS2

.subckt SwitchS2 1 2 V2 5 0 DC 0R1 5 6 20V1 6 0 DC 0W0 2 1 V1 NC_contact .MODEL NC_contact ISWITCH (Ion=0.05 Ioff=0.025 Ron=1e-8 Roff=1e30).ENDS

*## Multisim Component S1 ##** !!!BEGIN-INTERACT* 2.0 constant high* 0.0 constant low* 2 constant max_states* low VARIABLE volt** :MAP_KEYBOARD_INPUT ++++K1 1 ++++k1 -1 ;** : UPDATE_SETTINGS* *animation_state max_states low high STATE volt * GRADUAL_CHANGE_AT_RUN * ;** :KEYBOARD_INPUT locals| shift_state |* shift_state *animation_state max_states NEXT_STATE_WRAP* ==>_*animation_state* UPDATE_SETTINGS* ;** :GRADUAL_CHANGE_AT_RUN locals| ref value |* value SET_INSTANCE Vsource ::V V2 dc* ;** : INIT_IMOUSE_OPTION* 1 0 4 IMOUSE_SET* ;** : GET_IMOUSE_SUBCOMPS ( -- [iIdxN ... iIdx1] )* 1* ;** : ON_SUBCOMP_IMOUSE_EVENT locals| eEventType nOptions iSubCompIdx |* eEventType 2 = if* -1* -1 KEYBOARD_INPUT* else* 0* endif* ;** ( Initialize the settings )* UPDATE_SETTINGS* INIT_IMOUSE_OPTION** :BEGIN_PLOT* UPDATE_SETTINGS* ;** :BEGIN_ANALYSIS* UPDATE_SETTINGS* ;** !!!END-INTERACT

xS1 8 0 SwitchS1

.subckt SwitchS1 1 2 V2 5 0 DC 0R1 5 6 20V1 6 0 DC 0W0 2 1 V1 NC_contact .MODEL NC_contact ISWITCH (Ion=0.05 Ioff=0.025 Ron=1e-8 Roff=1e30).ENDS

*## Multisim Instrument XSC1 ##*

*## Multisim Component R2 ##*rR2 5 9 47000 vresR2 .model vresR2 r( )

*## Multisim Component R1 ##*rR1 5 8 47000 vresR1 .model vresR1 r( )

*## Multisim Component C2 ##*cC2 3 0 1e-008

*## Multisim Component U2 ##*xU2 0 8 7 9 3 0 U2_OPEN_DIS 5 LM555__TIMER__1



*## Multisim Component U1 ##*xU1 4 5 0 LM7805CT__VOLTAGE_REGULATOR__1

*## Multisim Component C1 ##*cC1 4 0 0.00047

*## Multisim Component F1 ##** !!!BEGIN-INTERACT* : delay_factor ++++i2 ;* : imax 1.0 ;* 0 constant S_OK* 1e30 constant blown* 1e-3 constant Rinit* 0 VARIABLE cnt* 1 VARIABLE delaytime* 0 VARIABLE S_BLOWN* 0.0 VARIABLE resistance* 0.0 VARIABLE r1Cur* 0.0 VARIABLE r1TCur* 0.0 VARIABLE r1CurAC* 0.0 VARIABLE r1CurDC* 0.0 VARIABLE flag* 0 VARIABLE nTime* 0 VARIABLE nTimeCur** : DELAY* *delaytime 0 do* *cnt 1+ ==>_*cnt* *cnt *delaytime = if* *S_BLOWN 1 + ==>_*S_BLOWN* 0 ==>_*cnt* endif* loop* *S_BLOWN ==>_*animation_state* ;* : R_BLOWN* blown resistance GRADUAL_CHANGE_AT_RUN* ;** : RESET* delay_factor 10000 * ==>_*delaytime* 0.0 ==>_*flag* 0.0 ==>_*r1TCur* S_OK ==>_*animation_state* 0 ==>_*S_BLOWN* Rinit resistance GRADUAL_CHANGE_AT_RUN* 1 RESET_ACDC* 2 RESET_ACDC* GET_LOCAL_TIME ==>_*nTime* ;* :GRADUAL_CHANGE_AT_RUN locals| ref value |* value SET_INSTANCE Resistor ::R r1 resistance* ;* :BEGIN_PLOT* RESET* ;*** :OUT_DATA* 1.0 *flag f.> if* GET_INSTANCE Resistor ::R R1 i ==>_*r1Cur* (( *r1Cur )) 1 ADD_ACDC* (( *r1Cur )) 2 ADD_ACDC* GET_LOCAL_TIME ==>_*nTimeCur* *nTimeCur *nTime - 6 >= if* (( 1 GET_DC )) ==>_*r1CurDC* (( 2 GET_AC )) ==>_*r1CurAC* *r1CurDC f.abs *r1CurAC f.+ ==>_*r1TCur* *nTimeCur ==>_*nTime* endif* imax *r1TCur f.< if* 1.0 ==>_*flag* DELAY* DELAY* DELAY* DELAY* DELAY* DELAY* R_BLOWN* endif* endif* ;* : BEGIN_ANALYSIS* RESET* ;** 1 ACDC::ALLOC_INDEX* 2 ACDC::ALLOC_INDEX** : SIMULTATION_CHANGED* ACDC::CIRCUIT_CHANGE* GET_LOCAL_TIME ==>_*nTime* ;** !!!END-INTERACTxF1 6 1 virtual_fuseF1.subckt virtual_fuseF1 1 2R1 1 2 1e-3.ends

*## Multisim Component D4 ##*dD4 2 4 1N4007__DIODE__1




*## Multisim Component T1 ##*xT1 12 13 6 2 Tran_T1.subckt Tran_T1 p1pos p1neg s1pos s1neg***Primary coil 1G1 p1pos p1neg value={-1/10*(1*I(Es1))}

***Secondary coil 1Es1 s1pos s1neg value={V(p1pos,p1neg)*1/10}

.ends

.subckt LM555__TIMER__1 0 2 3 4 5 6 7 8 rn1 8 5 5krn2 5 51 5krn3 51 0 5kaop1 %vd(5 6) 56 opaop2 %vd(2 51) 52 op.model op limit (gain= 3000, + out_upper_limit=5, + out_lower_limit=-5, + limit_range=1 fraction=true)aadc1 [56 52] [r s] ADC1.MODEL ADC1 adc_bridge (in_low= 2.5 in_high = 2.5 rise_delay= 1e-12 fall_delay= 1e-12) anand1 [r Q2] Q1 nand1anand2 [s Q1] Q2 nand1.model nand1 d_nand(rise_delay=1n)adac1 [q1 q2] [66 62] DAC1rad3 66 0 1rad4 62 0 1aadc4 [4] [40] ADC1ainv2 40 41 inv1adlatch q1 2u 41 3d Qb Qc dlt.model dlt d_dlatch(rise_delay=1e-12)apu1 2u pullup1.model pullup1 d_pullup(load=10e-12)apd1 3d pulldown1 .model pulldown1 d_pulldown(load=10e-12)ainv1 Qb 31 inv1.model inv1 d_inverter(rise_delay=1e-12)adac72 [Qb] [72] DAC1 adac31 [31] [32] DAC1r30 32 0 1gb1 333 0 v=(v(32)*v(8)/5)r3 333 0 1gaslew %vd(333 0) %vd(3 0) Slew_Rate_Block.MODEL Slew_Rate_Block slew(+ rise_slope=10e+6+ fall_slope=10e+6).MODEL DAC1 dac_bridge (out_low= 0.0 out_high= 5.0 out_undef=0.5) rad5 72 0 1megrdisb 71 72 1 qdis 7 71 0 qdis .MODEL qdis npn ().ends

.SUBCKT LM7805CT__VOLTAGE_REGULATOR__1 3 1 2*************************************** Model Generated by MODPEX **Copyright(c) Symmetry Design Systems** All Rights Reserved ** UNPUBLISHED LICENSED SOFTWARE ** Contains Proprietary Information ** Which is The Property of ** SYMMETRY OR ITS LICENSORS ****************************************node 1: VREG (OUTPUT)*node 2: Ground (Common)*node 3: Line VoltageECCX 131 2 135 2 1.0VXX 133 2 DC 0FSET6 2 135 VSENS2 1FPP 3 2 VXX 1.0R_YY 31 2 1e6R_XX 15 2 1e8R_ZZ 36 2 1e6R_QQ 65 2 1e8RXX 1 2 1e8VSENS1 10 1 DC 0ISET 2 15 DC 1e-3DON1 15 16 DMOD1VSENS2 16 19 DC 0DON2 15 17 DMOD1EON2 18 2 3 2 1FYY 3 2 VSENS1 1DON3 15 27 DMOD1VDROP3 28 27 DC 2EON3 28 2 3 2 4ELINE 13 42 66 2 1FSET2 2 36 VSENS2 1DSC1 36 35 DMOD1RCL1 36 37 10DSC2 37 38 DMOD1ESCCON 38 39 30 2 1VSCCON 39 40 DC 0FSC 19 2 VSCCON 1FSET3 2 31 VSENS2 1DOV1 31 32 DMOD1EOV1 32 2 3 1 1DOV2 31 33 DMOD1ISET4 2 30 DC 1e-3ELOAD 41 2 77 2 -1ERIPPLE 42 41 72 2 1EREF 12 13 19 2 1E3 52 2 3 2 1CBYPS 54 2 0.001VORB 54 60 DC 0RB 60 2 1e3RBR 72 2 1000CBS2 52 71 1RSTEP 77 2 1FRB 2 65 VORB 1DRB2 65 67 DMOD1VXRB 67 68 DC -1EXRB 68 2 1 2 1DRB1 65 66 DMOD1RB1 66 2 1000.MODEL DMOD1 D*-- DMOD1 DEFAULT PARAMETERS*IS=1e-14 RS=0 N=1 TT=0 CJO=0*VJ=1 M=0.5 EG=1.11 XTI=3 FC=0.5*KF=0 AF=1 BV=inf IBV=1e-3 TNOM=27EXX 132 131 3 131 0.0444444RST6 135 2 10000RIQX 133 132 RQIX 2222.22.MODEL RQIX R TC1=-0RSET 19 2 RSET 5000.MODEL RSET R TC1=1e-05 TC2=-1.5005e-06RS1 10 12 0.0075VDROPX 18 17 1.46HSENSE1 35 2 VSENS1 4.16667RISC 30 2 RISC 10000.MODEL RISC R TC1=-0.0025ROV 34 2 20000VOV 33 34 10EOV2 2 40 34 2 0.291667FIQD 3 2 VSENS1 0.0003RY 52 54 5e+06RA 72 73 2162.75RYR 71 72 9.999e+06CRA 52 73 1.59136e-11HSTEP 76 2 VSENS1 1CSTEP 76 77 6e-06.ENDS

.MODEL 1N4007__DIODE__1 d (+IS=3.19863e-08 RS=0.0428545 N=2 EG=0.784214+XTI=0.504749 BV=1100 IBV=0.0001 CJO=4.67478e-11+VJ=0.4 M=0.469447 FC=0.5 TT=8.86839e-06+KF=0 AF=1 )

Bistable Multivibrator

Documents

Transcript of Bistable Multivibrator