confusion
Junior Member level 3
1)i am using pic16f877a to interface interface 8 leds to it.. the pic16f87x datasheet says that its high sink/source current is 25ma. and i am using red leds which sinks in at the max 30ma current. as i am using 8 leds 30x8=240ma+25ma=265ma will be needed by the kit at the most..
2)this is how i calculated the current requirement for the source(i might be wrong ..so plz correct me).. so know i am using a 9v battery(6f22) which has typical current rating of 400ma. which satisfies my requirement.
3)then i connected a 7805 regulator(500ma typical current rating) to power the pic ckt . so when i give a 9v i/p to the regulator i get o/p somewhere equal to 4.95-5v . but when i give it to the pic ckt it shows me 0.82v accross the supply terminals and at the vss and vdd of the supply.
and battery gets discharged fast.. after that the battery showed only 5.54v accross it.
is the battery not sufficient to provide current to the 8 leds ? what might be the problem.
.plz reply as soon as possible
thanx in advance!!
2)this is how i calculated the current requirement for the source(i might be wrong ..so plz correct me).. so know i am using a 9v battery(6f22) which has typical current rating of 400ma. which satisfies my requirement.
3)then i connected a 7805 regulator(500ma typical current rating) to power the pic ckt . so when i give a 9v i/p to the regulator i get o/p somewhere equal to 4.95-5v . but when i give it to the pic ckt it shows me 0.82v accross the supply terminals and at the vss and vdd of the supply.
and battery gets discharged fast.. after that the battery showed only 5.54v accross it.
is the battery not sufficient to provide current to the 8 leds ? what might be the problem.
.plz reply as soon as possible
thanx in advance!!