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So in my electronics textbooks I see brief mentioning of PNP transistors but very little description of current flow and there are no actual equations or formulae for calculating collector current, collector voltage, and V[CE](collector-emitter potential difference). So how does one compute these properties and how do they differ in transistor action from NPN transistors(which are far more common)?

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NPN and PNP transistors work essentially the exact same way. PNP's just reverse the voltage and current flow. So for an NPN, to bias it on you have the base at 0.7V ABOVE the emitter, for a PNP you would have the base 0.7V BELOW the emitter. For an NPN, current flows INTO the base. For PNP, current flows OUT of the base.

Current flow is also reversed. In an NPN collector current flows into the collector and out the emitter. In a PNP it goes in the emitter and out the collector. But other than that the basic equations apply equally to both.

One other thing, in general PNP's are slower and have lower gain than NPN's but this is becoming less true as fabrication processes improve

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Actually they are same. Just reverse some sign and change some parameter. A book from streetman illustrates this part with the example of PNP rather than other book with NPN.

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