Trannies as diodes, does PNP, NPN matter?

[tungngruv]

When using a sil. or germ. trannie as a diode, does it NPN or PNP make a difference or can both types be used in any circuit as long as it's being used as a diode only? Thanks for any ideas about this.

[smccusker]

Whoops, I didnt read the question properly.  :oops:

[R.G.]

No perceptible difference to any circuit we're likely to use.

Remember that the collector-base junction is a high voltage/low leakage junction better for diode use than the low voltage (about 6V) of the base emitter junction.

BE's make fine 5-7V zeners if you're willing to take pot luck on the voltage.

[petemoore]

note of course the arrow in the transistor data sheet that indicates diode direction and PNP or NPN.

[tungngruv]

My understanding (which is probably incorrect) is that to use an PNP transistor instead of an NPN, you have to reverse the poliarity of all the electrolytic caps, and also put the transistor in backwards.

I think it's just reverse all polarity of electro's, diodes and battery when used normally as trannies. As diodes, so as long as I connect the base/emitter and use the collector as negative, both NPN and PNP can be used as diodes, right? Thanks again!! Thanks R.G.!!!!