Reversing the polarity of a power supply

Thread Starter

true bypass

Joined May 17, 2008
8
I'm trying to reverse the polarity of a circuit which normally is positive grounded. I want it to be negative grounded.

I think this should do it, but am unsure, can someone please tell me if this will work or not? Am I missing something?
 

bloguetronica

Joined Apr 27, 2007
1,541
Besides using NPNs insead of the PNPs, like beenthere said, you should invert the electrolytic capacitors (10uF and 25uF) as well. That way, they will not explode when you turn your circuit on.
 
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bloguetronica

Joined Apr 27, 2007
1,541
but, if i for some reason wanted to use PNP's, is this circuit right?
You have to use the transistors in common emitter configuration, like proposed in the circuit. That is why PNPs won't work.

In the article you've shown, he is using the battery in a manner that the current biasing the transistor will flow in the same way. He is using a negative ground now but the ground is connected to the collectors of the transistors, making the circuit essentially the same. Of course it is bad construction practice having a ground plane connected to the collectors of the transistors, since a ground plane is a large conductor and will bring some oscillation. He even mentions that, but a good construction practice is not what he mentions.
 
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