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Design >> Analog Design >> cmos amplifier
https://designers-guide.org/forum/YaBB.pl?num=1367075362

Message started by aman gupta on Apr 27^th, 2013, 8:09am

Title: cmos amplifier
Post by aman gupta on Apr 27^th, 2013, 8:09am

plot transfer characterstics ........... PMOS transistors are identical
my actual question is can Vi put Q2 in triode region ?? if yes then how ?

Title: Re: cmos amplifier
Post by raja.cedt on Apr 27^th, 2013, 9:58am

hello,
Very low voltage at the gate of Q1 leads to very high voltage at Q2 hence it will be in triode region.

Enjoy!!!

Title: Re: cmos amplifier
Post by aman gupta on Apr 28^th, 2013, 5:55am

raja.cedt wrote on Apr 27^th, 2013, 9:58am:

hello,
Very low voltage at the gate of Q1 leads to very high voltage at Q2 hence it will be in triode region.

Enjoy!!!

because Q1 is common source which is inverting, hence very low at Vin cause a large voltage at Vd2 ??? am i right ??

Title: Re: cmos amplifier
Post by raja.cedt on Apr 30^th, 2013, 12:37pm

yes, otherwise if you increase Vin Q1 draws more current and out voltage will be lower and other way also when Vin decrease. Again please refer razavi book.

Thanks,
Raj.