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Design >> Analog Design >> Designing Discrete OpAmp
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Message started by soso on Jun 21^st, 2016, 11:56pm

Title: Designing Discrete OpAmp
Post by soso on Jun 21^st, 2016, 11:56pm

I am trying to analyse a discrete differential amplifier circuit by answering some question. I have done the analysis of the input stage, I would appreciate if I can get some feedback on my approach.

Kind regards

Title: Re: Designing Discrete OpAmp
Post by soso on Jun 22^nd, 2016, 7:12am

Here is my analysis of the differential input stage

Title: Re: Designing Discrete OpAmp
Post by soso on Jun 22^nd, 2016, 7:16am

Here is the analysis of the PNP transistors in the input stage

Title: Re: Designing Discrete OpAmp
Post by soso on Jun 22^nd, 2016, 7:19am

Solution

Title: Re: Designing Discrete OpAmp
Post by soso on Jun 22^nd, 2016, 7:24am

Solution continues

Title: Re: Designing Discrete OpAmp
Post by soso on Jun 22^nd, 2016, 7:38am

Part three of solution

Title: Re: Designing Discrete OpAmp
Post by soso on Jun 22^nd, 2016, 7:54am

Part 4 of solution

Title: Re: Designing Discrete OpAmp
Post by loose-electron on Jul 6^th, 2016, 10:28pm

You need to look at 3 solutions - high common mode voltage, low C M V and middle range

they are 3 different things.

Also, why not just do a small signal model at the bias point?