8 hour timer - PIC or 555 with counter

[isaac12345]

Hi,

I need an 8 hour timer for a battery charging circuit and was wondering which one would be better - a PIC with an 8 hour time delay or a 555 timer with a counter.

 

[IanP]

It’s easier to realize 8-hour timer with a PIC (or PICAXE) and it’s also more reliable ..

Have a look at this example:
https://www.electro-tech-online.com/micro-controllers/29302-1-hour-timer-pic-16f628a-set-button.html

Rgds,
IanP

 

[GrandAlf]

There used to be an 8 pin IC for automotive use, that had capability from 3.7 secs to many hours, it had a built in ripple counter so that timing components could be small and more accurate. I really cannot now remember the part number, which is a pity, as they were very reliable in noisey enviroments. You may be able to find something similar, otherwise go for Pic etc, 555 would be rubbish for this application.