Please Help.... Timer Circuit Needed.

[Pixie M8]

I am fairly new to electronics and need to design and build a circuit that will countdown from a set hour to zero and flash a light until a reset button is pushed.

to start the timer a person must choose the time duration, from an hour to 24 hours and then press a start button to start the countdown.

when the counter reaches zero after the set hours the circuit then flashes a light to indicate that the desired time has elapsed..

I would be very grateful for any assistance that anyone can give me on this project

Thanks :roll:

 

[mozikluv]

timer circuit

hi there,

you said you want to design a timer circuit that could run up to 24 hrs. well here an ic timer (CD4536) that could run up to 36 hrs. its a 24bit binary ripple counter w/16 stages selected by a 4bit binary code. check the datasheet of this device so you may identify the pin configuration. also you can choose to use external clock or its internal oscillator.

 

[leprien]

stop watch

well sounds like a bit of work to make the circuit if thats all you want it for. I would take apart a cheap stop watch and sodder conections to the display inputs and record whats hot when certain numbers are displayed use this out put to run any circuit that would be subsiqeunt to it.