interchangeable power supply

[ernestclydeachua]

hi guys im creating an interchangeable power supply, im having problems on energizing a 6v relay which exceeds the output voltage of pic16f84a i dont know how to build an amplifier like a common emitter amp can someone help me how to build a common emitter amp and what components should be used?

 

[Textinstar]

hopefully this helps

Not sure if I understand you needs correct but hopefully this helps.
2N3904 or BC547 are fairly common NPN transistors, but pretty much any NPN will do.
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[alec_t]

im having problems on energizing a 6v relay which exceeds the output voltage of pic16f84a

I'm not surprised. Not only is the PIC output voltage too low but the PIC probably couldn't provide enough current for the relay coil either. If I've understood what you're trying to do then you need an auxiliary power supply (wall wart?) for the relay and a transistor controlled by the PIC to switch the relay.