How to build 24 digital clock using 74-163 IC?

Thread Starter


Joined Oct 27, 2009
Hello everyone..

I need help in this : Using the 74163 IC(s) and any necessary gates, design a 24-hours digital clock which is fed by a 1Hz Signal.

like 00:00:00
if the seconds are 59 it will be cleared then the minutes will count one...etc.
the way i tried it .. is to use for each "seonds ,minutes and hours" 2 ICs

then Implement the clock on LogicWorks, use the HEX display to show the time as HH:MM:SS.
how to use the Hex Display ??

The 74169 is a 4-bit synchronous up/down counter, download the datasheet for the counter .use this counter to simulate a circuit that generates the following sequence:
2,3,4,5,6 12,11,10,9,8 2,3,4,5,6 12,11,10,9,8 2,3,4,5,6 12,11,10,9,8 …. And repeat.

How to enable up and down counter ??

Thnx in advance ..

Thread Starter


Joined Oct 27, 2009
Thnx for ur precious Advice ! :)

i tried the second part which is the 74_169 counter and didn't get the result !

could anyone look at the circuit and tell me Wat's wrong :confused:.. i did it using logic works ,, and if anyone want the original file i can send if u ask ,,



Joined Feb 19, 2009
What is the output of the one above?

How I did this project many many years ago was to use 5 counters, with logic from the first one (seconds low) going through NAND/AND gates so when 12 was counted, 1 was output, a clock pulse went to the second counter (seconds high) and reset the first counter, the second counter did the same thing but counting to 5, then reset to 00, and clocked the next counter, which was two more cascaded (minutes low, minutes high) for 60 minutes, pulse out on 60, display 0, which clocked a final 0-12 counter.

Using different counters, the setup may change a bit, but that is the overall picture. Lowering it to only 3 counter IC's would be a great improvement for the display.


Joined Apr 20, 2004
You might find it easier to use a 74LS162 BCD counter, vice the '169, which is binary and harder to use. The up/down feature is not needed.

A decoder driver, like a 74LS47 is made to drive a 7 segment display.

Get data sheets to see how the IC's work