How to bias a PNP transistor?

Thread Starter

opa627bm

Joined Nov 26, 2011
16
Hello everyone,
I've found some PNP Ge transistors and want to build an audio amplifier from it. I used to work with NPN a lot and I know the way to bias them is to use a two resistor voltage divider. However, because the PN junction in PNP is reversed, the resistor divider dose not work anymore. I searched many website but none of them is talking about how to bias a PNP.
Can some one tell me how to correctly bias a PNP tranristor?

Best
Lee
 

Ron H

Joined Apr 14, 2005
7,063
Hello everyone,
I've found some PNP Ge transistors and want to build an audio amplifier from it. I used to work with NPN a lot and I know the way to bias them is to use a two resistor voltage divider. However, because the PN junction in PNP is reversed, the resistor divider dose not work anymore. I searched many website but none of them is talking about how to bias a PNP.
Can some one tell me how to correctly bias a PNP tranristor?

Best
Lee
If you take a good NPN design, and change the power supply from positive to negative, it will work. You will have to reverse the polarities of polarized capacitors also.
 
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