View Single Post
  #7   Report Post  
Posted to sci.electronics.repair
Charon Charon is offline
external usenet poster
 
Posts: 7
Default Repairing/understanding PNP in charging circuit

On Apr 19, 1:56*pm, Jeff Liebermann wrote:
On Sun, 19 Apr 2009 00:37:39 -0700 (PDT), Charon
wrote:

I have a small circuit and I think I may have crossed something and
wrecked a transistor. I'm pretty much self teaching and want to see if
I have this figured out properly


Welcome to "Learn By Destroying(tm)". *You're off to a great start.

The PNP, only the C and E are soldered to anything, the Base is not
connected to anything. Why would this be ?


Because it's probably a power FET and not a PNP transistor. *Are there
any identifying marks on the device? *A photograph perhaps?

Doesn't electric charge flow on C and E if there is no flow on base ?


Electrons flow from negative to positive.
Holes flow from positive to negative.
PNP transistors have the collector more negative than the emitter.
Therefore, electrons will flow from collector to emitter in a PNP.
It's the same if you think of "electric charge flow" as the flow of
electrons. *If you're confused, you have plenty of company. *This
might help:
http://www.tpub.com/neets/book7/25b.htm
(or make things worse).

Did this transistor go bad ?


I don't think the transistor went anywhere. *It's still in front of
you. *Where did you expect it to go?

--
Jeff Liebermann * *
150 Felker St #D * *http://www.LearnByDestroying.com
Santa Cruz CA 95060http://802.11junk.com
Skype: JeffLiebermann * * AE6KS * *831-336-2558