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Design >> Analog Design >> Differential current input amplifier
https://designers-guide.org/forum/YaBB.pl?num=1520491571

Message started by ttwwjj on Mar 7^th, 2018, 10:46pm

Title: Differential current input amplifier
Post by ttwwjj on Mar 7^th, 2018, 10:46pm

Hi guy,

I saw this amplifier at work and a text book.

My textbook just claims that it is good and try to use it without any detail analysis and references. Can anyone explain how it works or give any related references?

thx

Title: Re: Differential current input amplifier
Post by Jacki on Mar 14^th, 2018, 12:52am

I think it depends on your application, if you need a single-ended or differential current amplifier. The theory is basic current mirror, you keep the gate voltage stable for the four transistors, and input the signal voltage at the source. For common mode input voltage, the input impedance is very high, but for differential mode input voltage, the input impedance is 1/gm.