I am making Digital alarm clock, i have uploaded circuit diagram of digital clock, i want to ask that how can i make it alarm clock?
which IC should I use?
Please Help me out..

 

That is a lot of work and chips to make an alarm clock. The only reason one would design a clock in this manner is to learn how digital counter circuits work.

You can make a digital alarm clock with one mcu chip.

 

This is my project of Digital logic Design,
so i can not use any type of micro controller.

 

So this is homework project. Adding an alarm feature would be extremely complicated.

You could limit the alarm to trigger on the hour only.

 

Hello,

You could start reading things about digital logic in the links presented on the following pages:
Digital logic
Digital theory
Counters & registers

Bertus

PS : Don't use your email-adresses as user name.

 

You could use 74LS85 magnitude comparators that compare the BCD hours and minutes to values set on thumbwheel BCD switches to hold the alarm time. A=B is the alarm output.

The alarm time could also be the outputs of 4 more 7490's (or some BCD up/down counter) that uses buttons to count to the desired alarm time in the same manner that you set the time of day. In that case, you would need to multiplex the digit values between the alarm and time registers so that you could see the alarm setting.

 

The brute force way would be to take two of these clocks and disable the clock signal for one of them (assuming that you can still set the time without it, which I can't tell because I can't read the schematic details well enough). Then use a quad XOR gate for each digit (or perhaps just the hourse and minutes) to compare the values on the two clocks. Combine all of the digits with NOR and you have a signal that goes HI only when the output of the two circuits match. Use that for your alarm trigger.

 

hey man, have u gotten solution for ur digital alarm clock design? if so please help me by attaching it. coz u know i'm on agreat confusion on it and i need a help of espeasially yours. and make it fast
THANK YOU

 

Watch your language and tone of voice.

The purpose of AAC is to help each other learn and not to serve you on a silver platter pronto.

Also when someone chooses to type using single letters, poor spelling and punctuation it tells us a lot about his/her personality

 

hey man, have u gotten solution for ur digital alarm clock design? if so please help me by attaching it. coz u know i'm on agreat confusion on it and i need a help of espeasially yours. and make it fast
THANK YOU

In other words, "Yo Dude, I want to copy your homework. Give it to me now!"

 

schematics with many wires