Re: Question about transistor substitutions.



On 21 Aug 2005 10:15:09 -0700, ngdbud@xxxxxxxxxxx wrote:

>In most circuits could a 2n3904 be used in place of a 2n4401, and a
>2n3906 in place of 2n4403? 906 is the pnp and 904 is npn, right?

The 3906 is a PNP and the 3904 is an NPN. So yes. Also, the 4401 is
an NPN and the 4403 is a PNP. I'd imagine that for most common
purposes, the NPNs and PNPs could be exchanged for each other. Their
forward betas are similar, junction capacitances aren't too far apart,
etc.

Jon
.



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