tarantulataramasalata
Senior Member
hello
please help - i am trying to troubleshoot a circuit but I am really stuck.
I have a pic chip outputting to 2 4511bs, and then to a pair of 7seg leds for counting up to 99, powered by 2 3v lithium coin cells.
I have checked the circuit a squillion times, everything is wired properly and there's no shorts. I have replaced all chips and the 7seg displays work.
however, as soon as it is turned on, the voltage across the cells drops to about 3v, which implies that there is a problem somewhere, but I have run out of ideas where to look.
however, one of the 7 seg leds works absolutely fine, the other doesn't. the pic chip doesn't seem to be outputting on that side.
any help you can offer, as ever, very appreciated
please help - i am trying to troubleshoot a circuit but I am really stuck.
I have a pic chip outputting to 2 4511bs, and then to a pair of 7seg leds for counting up to 99, powered by 2 3v lithium coin cells.
I have checked the circuit a squillion times, everything is wired properly and there's no shorts. I have replaced all chips and the 7seg displays work.
however, as soon as it is turned on, the voltage across the cells drops to about 3v, which implies that there is a problem somewhere, but I have run out of ideas where to look.
however, one of the 7 seg leds works absolutely fine, the other doesn't. the pic chip doesn't seem to be outputting on that side.
any help you can offer, as ever, very appreciated