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Old 10th Dec 2017, 1:39 am   #27
Argus25
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Join Date: Oct 2016
Location: Maroochydore, Queensland, Australia.
Posts: 2,679
Default Re: Matched Transistors

Quote:
Originally Posted by mhennessy View Post
The input impedance of each transistor is hFE/gm.
I still tend to prefer transistor analysis as though they were current amplifiers rather than transconductance devices, since the input impedances are low and the input currents not insignificant, most of the time, but it is personal preference and each has advantages/disadvantages.

If you want a rough calculation of the hfe:

see next post

Last edited by Argus25; 10th Dec 2017 at 1:53 am. Reason: Had to make corrections
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