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Programmable Third Brake Light Flasher - PIC12F629


New Member
Thanks kchriste.
In the darlington pair, I see there are two resistor built in. Each of the transistor has one resistor across the base and emitter as attached.
So the 200 :eek:hm: resistor is used for the purpose that we were discussing, then what about the 5 k:eek:hm: resistor? Same purpose? To prevent any leakage current to the base of the transistor to turn it on?



New Member

hi ...

is this possible to modified the signal out from PIC to be in negative ?
2n222 is NPN --- base bias current is + (P)

since i have the 2 main light with common negative (-) so i can not use the NPN, if i use this the other lamp will be screw up.

my idea is driving the output signal from PIC dirrect to P chanel mospec.

i am testing the diagram above with N chanel mospec and it's work perfectly without using the 2n222 as a driver and without any resistor -- (for simplest way) LOL ....

tested with buld instead of led and the speed is prety good.

any idea ??
Last edited:


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