Digital Stopwatch Circuit, Feature : Durable

Listing ID #964200

We are offering Digital Stopwatch Circuit. Electronics has its impact on almost every field today. The 'digital stop watch ' described here finds application in sports and different fun games where even a fraction of second matters a lot. through this project we can count even the 110th of a second. The counter immediately stops counting once the stop switch is pressed and when the reset switch is pressed we again have 000 display in the 7-segment display. the project mainly employs two timer ic555 (ic1 & ic2), three decade counter ic4033 (ic3, ic4 & ic5) and 7-segment displays in common cathode configuration. About the circuit: in the circuit diagram, ic1 is used in bistable mode and ic2 is used in astable mode. when the start switch is pushed on, ic1 is triggered, its output at pin3 goes high which in turn is applied to reset pin4 of ic2. Hence ic2 is operating in the astable mode and it will generate pulses of frequency 10hz. The frequency is determined by the rc time constant of the circuit. The output at pin3 of ic2 is applied to clockin (pin1) terminal of first 4033 ic i.e. Ic3. This ic being a decade counter starts counting from 0 to 9. The corresponding 7-segment display thus shows 0.1 seconds of measurement. After counting from 0 to 9 this ic will generate pulse at clockout (pin5) terminal, which is connected to the clockin terminal of second ic4033 (ic4). Thus ic4 starts counting from 0 to 9. The corresponding 7-segment display connected to ic4 display each second. The third 4033 ic (ic5) also receives pulse at clockin terminal in similar manner and counting starts. As long as the stop switch is not pressed the stopwatch keeps on counting. The watch can count maximum up to 99.9 seconds. The circuit being a decade-up counter, after counting 99.9 seconds all three displays shows 000 and the process of counting repeats. if the stop switch is pressed at any instant between the counting,output of ic1 goes low and correspondingly the reset pin of ic2 receives a negative going pulse and output goes low. So all three counters stops counting. the reset pins of all the three 4033 ic's are connected together, so when reset switch is pressed all three counters gets reset. here led d1 connected at output pin3 of ic2 indicates that the output pulsesclock pulses are generated and circuit is operating properly.