Digital Counter

8683R DIGITAL AND ANALOGUE DEVICES AND CIRCUITS EED 3303

ACKNOWLEDGEMENT Alhamdulillah Alhamdulillah and grateful to Allah S.W.T the Al-Mighty cause give me an oppo opportu rtunit nityy of manag managing ing the spec specifi ificc time time to compl complet ete e this. this. Witho Without ut Allah Allah permission definitely I cannot done my project. We can just try and pray but only Allah can decide decide it. Firstly, I must try all my best, but I know I still at back that why I need and I must try hard with have patience inside me. I know that I must strive forward like ask further information information from lecturer and get knowledge from them. I hope in this way I can improve myself with more encouragement and enjoyable for this subject. Not forgot to all my friend who help me when I got trouble and give me a spirit to get more interesting interesting in this subject, meanwhile to my senior who are give me an advice for this subject that really important for getting a job next. I hope that when I done this project the knowledge of this project not just disa disapp ppea ears rs and and I alwa always ys can can refe referr it back back and and give give me the the know knowle ledg dge e to extending my educational higher level and also useful as an experience for the future coming. I accept equal responsibility for this texts strength and weaknesses .The entire good thing came from Allah and the weakness is from my own weakness, because it is natural human been. Lastly, I hope that my lecturer always supports me to go forward, and I get more interesting to learn more for have the credibility and creativity in this subject.

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INTRODUCTION

A synchronous binary counter has the same sequence of count states as a ripple counter. However, if a flip-flop changes state when a synchronous counter is incremented, the chance occurs on the leading or trailing edge of a clock pulse rather than on the leading or trailing edge of the preceding flip-flop’s output As is characteristic of all synchronous devices, the clock is connected to every flip-flop in the counter, and all those flip-flop that change state do so at the same time. In a synchronous counter, the flip-flop are most often of the J-K type. The circuit is a synchronous counter that will count up 00 to 99, then down 99 to 00, then up 00 to 99. There are 3 type of Integrated Circuit use in this circuit (SN 7447, 74LS192, and 74LS04). It also can be manually stop and reset by an externally push button. The circuit can be divided into two sections. One section is called the unit counter; the other is the decade counter. There are 4 types of Integrated Circuit (IC) used in this circuit, 74LS192, SN 7447, 74LS04 and 555. 74LS192 IC is a synchronous BCD up/down counter. It is used to count up/down the binary output. SN7447 IC is a BCD to seven-segment decoder. It is used to connect the output from 74LS192 to a seven-segment display. The type of seven-segment display that has been used is common cathode seven-segment display

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555 is a timer IC. The clock from the IC will replace the clock from the digital trainer. Seven-segment display is used to view the output of the circuit. Instead of the output is display in binary state, the seven –segment display can display it in decimal state without any requirement of translating binary to decimal or any other format.

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UP/DOWN SYNCHRONOUS COUNTER CIRCUIT

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SIMULATION OF THE CIRCUIT

Up Counter

When the up counter switch is turn on, the seven-segment LED will display the output from decimal 00 to 99. Then it will return to 00 and perform the same operation over and over again. It will also count the output from any decimal number until it reach 99. The clock is connected to pin 5 (up) and +Vcc is connected to pin 4 (down) which will make the circuit become an up counter. IC 74LS192 will received a clock from the timer IC. This IC will count up from 0 for a unit counter. When the unit counter reached to 9, pin 12 and 3 will generate the clock to the second IC 74LS192 at below. This second IC will start count up from 0 for a decade counter. Then the circuit wills continuous count up from 00 till it reached to the highest value 99.

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Down Counter

When the down counter switch is turn on, the seven-segment LED will display the output from decimal 99 to 00. Then it will return to 99 and perform the same operation over and over again. It will also count the output from any decimal number until it reaches 00. The clock is connected to pin 4 (down) and +Vcc is connected to pin 5 (up) which will make the circuit become a down counter. IC 74LS192 will received a clock from the timer IC. This IC will count down from 9 for a unit counter. When the unit counter reached to 0, the pin 12 and pin 13 will generate the clock to the second IC 74LS192 at below. This second IC will start count down from 9 for a decade counter. Then the circuit wills continue count down from 99 till it reached to the lowest value 00.

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Reset condition

When the clear switch is turn on, the seven segments LED will reset back to 00. This condition applies to both up and down counter. This is cause by the Vcc which is connected to clear (pin 14) on the 74LS192 IC make the IC to reset to its original condition. But, when the reset button was pushed, the voltage supply will flow through the pin 14 for both of IC 74LS192. When the voltage enters to both of this IC, it will automatically reset the counter circuit. So, when the counter circuit is reset the seven segment will display 00 as at above.

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ANALYSIS Synchronous Counter

A Synchronous binary counter has the same sequence of count states as a ripple counter. However, if a flip-flops changes state when a synchronous counter is incremented, the change occurs on the leading or trailing edge of a clock pulse rather than on the leading or trailing edge of the preceding flip-flops output. The characteristic a synchronous, the clock is connected to every flip-flop in the counter. In a synchronous counter, the flip-flops are most often of under normal operating conditions, the J and K inputs to each flip-flop should remain stable at either logic 1 or 0 while the count pulse undergoes its 1 to 0 to 1 transition. Logic 1 on the clear control line will force all counter outputs to logic 0 and hold them there until the clear line is returned to logic pulses and leave the counter in some nonzero state, if such data-hold behavior is required for particular application the J-K typ e.

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COMPONENT IN THE CIRCUIT 74LS192

A 74LS192 IC is a synchronous BCD up/down counter. Synchronous operation is provided by having all flip-flop clocked simultaneously so that the output change coincidently with each other

Pin Diagram Pin Configuration: Pin 5

= CPU (Count Up Clock Pulse Input)

Pin 4

= CPD (Count Down Clock Pulse Input)

Pin 14

= MR [Asynchronous Master Reset (Clear) Input]

Pin 11

= PL [Asynchronous Parallel Load (Active LOW) Input]

Pin (1, 9, 10, 15) = P n (Parallel Data Input) Pin (2, 3, 6, 7)

= Q n (Flip-Flop Outputs)

Pin 13

= TCD [Terminal Count Down (Borrow) Output]

Pin 12

= TCU [Terminal Count Up (Carry) Output]

Pin 8

= Gnd (Terminal Ground)

Pin 16

= Vcc (Input Voltage Terminal)

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SN7447

A SN7447 IC is BCD to seven-segment decoder.

Pin Diagram Pin Configuration: Pin 3

= LT (Lamp Test)

Pin 5

= RBI (Ripple Blanking Input)

Pin 4

= BI/RBO (Blanking Input/Ripple Blanking

Output) Pin (1, 2, 6, 7)

= Input Terminal

Pin (9, 10, 11, 12, 13, 14,15) = Output Terminal Pin 8

= Gnd (Ground Terminal)

Pin 16

= Vcc (Input Voltage Terminal)

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555 Timer IC

555 is a timer IC. It will replace the clock from the digital trainer.

Pin Diagram Pin Configuration: Pin 1 = Gnd (Ground Terminal) Pin 8 = Vcc (Input Voltage Terminal) Pin 3 = Output (Clock/Timer Output)

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74LS04

74LS04 is an inverter IC. It has 6 inverter gates inside an IC. It will invert the input to the opposite condition as it output. (0 to 1, 1 to 0).

Pin Diagram Pin Configuration: Pin 1 = First Input (A0) Pin 2 = First Output (Ā0) Pin 3 = Second Input (A1) Pin 4 = Second Output (Ā1) Pin 5 = Third Input (A2) Pin 6 = Third Output (Ā2) Pin 7 = Gnd (Ground Terminal) Pin 8 = Forth Input (A3) Pin 9 = Forth Output (Ā3) Pin 10 = Fifth Input (A4) Pin 11 = Fifth Output (Ā4) Pin 12 = Sixth Input (A5) Pin 13 = Sixth Output (Ā5) Pin 14 = Vcc (Input Voltage Terminal)

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Seven-Segment Display

The seven-segment display chosen for this project is common Anode.

Seven Segment Common Anode LED Display Physical Layout and Schematic Diagram

The type of seven-segment display that has been used in this project is a common cathode seven-segment display. This seven segment will turn on when connected with the BCD-Decimal decoder and input voltage. This sevensegment has 10 pins. Pin number 3 is connected to the input voltage. Pins are connected to SN7447 IC according to their description.

When the number zero is display, all of pin is turn on except for pin g. This means the input High are connected through all of pin (a, b, c, d, e, and f). While the input Low is connected through the pin g.

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When the number one is display, only pin b and c is turn on. This means the input High are connected through pin b and c only. While the input Low is connected through pin a, d, e, f, and g.

When the number two is display, the pin a, b, d, e, and g is turn on. This means that the input High is connected through this entire pin. While the input Low is connected through pin c and f.

When the number three is display, the pin a, b, c, d, and g is turn on. This means that the input High is connected through this entire pin. While the input Low is connected through pin e and f.

When the number four is display, the pin b, c, f, and g is turn on. This means that the input High is connected through this entire pin. While the input Low is connected through pin a, d, and e.

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W


When the number five is display, the pin a, c, d, f, and g is turn on. This means that the input High is connected through this entire pin. While the input Low is connected through pin b and e.

When the number is six displays, the pin c, d, e, f, and g are turn on. This means that the input High is connected through this entire pins. While the input Low is connected through pin a and b.

When the number seven is display, the pin a, b, and c is turn on. This means that the input High is connected through this entire pins. While the input Low is connected through pin d, e, f, and g.

When the number is eight displays, the entire pin a, b, c, d, e, f, and g is turn on. This means that the input High is connected through this entire pin.

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When the number nine is display, the pin a, b, c, d, f, and g is turn on. This means that the input High is connected through this entire pin. While the input Low is connected through the pin e.

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COMPONENTS LIST

This is the list of components that I used to complete my synchronous up/down counter. Component

Quantity

74LS192 IC

2

SN 7447 IC

2

Resistor (1k Ω & 10k Ω)

2

Metric Street Board (MSB)

1

Common cathode seven

2

segment display Reset switch Up/down switch

1 1

555 timer IC

1

Capacitor (22µF)

1

IC base (14 pins) IC base (16 pins)

3 4

CONCLUSION

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Price (RM)

Given by Lecturer Given by Lecturer Given by Lecturer Given by Lecturer Given by Lecturer 0.30 1.80 Given by Lecturer Given by Lecturer 0.90 2.40


After I finish this assignment, I get more knowledge and more information during do this assignment. What I get is I know how to design ripple counter. Before we design we must know the step that we must follow. The first step is we must do the state diagram. In here we know what mode that we want to design. With using this state diagram my work very easy and we can see what we need to do. The second step that we need to do is transition table. After we do this we must do the present and next present to get the output before using the Karnough Map. After we get the output then we put it in the Karnough map then we simplified it. After we have followed all the procedure we can design the MOD that we need. The type of IC that we need to use is 74LS47 and 74LS192. I also find the best way to troubleshoot my circuit counter with the lab assignment. This is because while I build my circuit at stripe board. I learn how to settle my problem. Such as connection between ic pin and other component. This lab assignment give me many experience and I can used this knowledge for build any circuit with greatest For my observation, when we design we can use any logic that we want. But if we want do the project we must use the simple logic because to save the budget. We also must be careful during do design because if we have a careless mistake we can get what the MOD that we want. Therefore that output also can get.

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Digital Counter

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