PNP Transistor Theory

jb33

New Member
I have A1015 PNP transistor on a circuit board used to power a 12V coil on a relay that allows AC to flow to a motor contactor. The emitter and base both have 12V, but the collector is floating around 2V which is not nearly enough to power the relay. I have tested the transistor with a meter and it checks good. Any ideas why this is happening if the transistor is good? Does the emitter voltage need to be higher? Maybe the problem lies with the TD62003AF 7Ch Darlington Sink Driver that sits in front of the transistor? Thanks in advance for any help!
 
If the base and the emitter are both at the same potential, then the transistor is OFF. Without a schematic diagram of the circuit, I have no idea if there is any way to turn the transistor on. Were you hoping I could jinn up a circuit in my head that would help you?
 
Part of what I'm doing is creating a schematic for the board, but I need to fix this issue first. Tomorrow, I can post the schematic I've created for the transistor/relay portion, which is the output to the motor contactor. I believe the transistors are being driven by the TD62003AF 7Ch Darlington Sink Driver which has a flip flop in front of that. I'll post some pictures tomorrow. Thank you for the reply.
 
Cookies are required to use this site. You must accept them to continue using the site. Learn more…