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Design >> Analog Design >> Telescopic Cascode in 65nm Tech.
https://designers-guide.org/forum/YaBB.pl?num=1344424985

Message started by Analog_Designer on Aug 8^th, 2012, 4:23am

Title: Telescopic Cascode in 65nm Tech.
Post by Analog_Designer on Aug 8^th, 2012, 4:23am

I have designed a Telescopic Cascode in the 65nm Tech. and I want to ask about something I don't understand in the phase plot attached are both the topology written on it the operating point data and the bode plot (Gain magnitude and phase)

Title: Re: Telescopic Cascode in 65nm Tech.
Post by Analog_Designer on Aug 11^th, 2012, 4:05am

Please somebody answer me. Does that mean that people don't know the answer ?

Title: Re: Telescopic Cascode in 65nm Tech.
Post by Ken Kundert on Aug 11^th, 2012, 6:05pm

It could mean that people are simply not bothering to open your rar file. Perhaps you would be better served if you simply posted the figures.

-Ken

Title: Re: Telescopic Cascode in 65nm Tech.
Post by Lex on Aug 13^th, 2012, 12:27am

So what is it about that you don't understand? The phase jumping 360 degrees? I assume you understand something like cos(a)=cos(a+n*2pi) with n element of Z?

Considering your circuit, you might want to increase the NMOS cascode voltage. In this way your CS stage'vds<vdsat.

Title: Re: Telescopic Cascode in 65nm Tech.
Post by Analog_Designer on Aug 13^th, 2012, 4:42am

I want to know why the sudden change in the phase like that? what causes it in the circuit?

Title: Re: Telescopic Cascode in 65nm Tech.
Post by Lex on Aug 13^th, 2012, 5:29am

It is not caused in the circuit. It is caused in the way the phase is calculated for the waveform viewer. Try to unwrap it ;)