I want to work on op-amps but linearity of the op-amps differential pair is very low. So to increase linearity I have read that there is a techinque to linearize the differential pair. whats the difference between using a passive resistor for source degeneration and MOS device in triode region to improve linearity.
If I use triode MOS for source degeneration then what gate voltage should I apply. What biasing circuit for gate voltage of triode MOS?
Op-amps are usually operated in feedback circuits that don't need linear input stages because the input voltage is zeroed. It's different e.g. for OTA. What do you want to achieve?
What do you mean by 'the input voltage is zeroed'. For the differential pairs of OP-AMP we also apply differential volatges then how input voltage is zeroed.
I am a grade1 student. I cant understand this point of yours.
I want to work on op-amps but linearity of the op-amps differential pair is very low. So to increase linearity I have read that there is a techinque to linearize the differential pair. whats the difference between using a passive resistor for source degeneration and MOS device in triode region to improve linearity.
If I use triode MOS for source degeneration then what gate voltage should I apply. What biasing circuit for gate voltage of triode MOS?
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whats the difference between using a passive resistor for source degeneration and MOS device in triode region
When you put resistor you cannot change it in real life. But when you use transistor you can switch it on or off and also change the linear resistance (rds) by changing the gate voltage so in second case you have made a variable gain amplifier.
Check Current stealing method also for linearizing your OTA or Opamp.
There are 2 methods which are popular:
1) Source Degeneration OTA
2) Current Stealing OTA
and also search for Source degenerated MOS transconductor using MOS transistors.