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Simulators >> Circuit Simulators >> Fully Differential Opamp Simulation with Switched Capacitor CMFB
https://designers-guide.org/forum/YaBB.pl?num=1513251390

Message started by repah on Dec 14^th, 2017, 3:36am

Title: Fully Differential Opamp Simulation with Switched Capacitor CMFB
Post by repah on Dec 14^th, 2017, 3:36am

Hello,

I am attempting to simulate this Fully Diffferential Opamp with SC CMFB.

I need to get the SNDR to 70dB.

Should I use Transmission Gates for the Switches shown in the figure below ? What strategies can I use to increase the SNDR ?

Thank you in advance for advice and tips.

Title: Re: Fully Differential Opamp Simulation with Switched Capacitor CMFB
Post by repah on Dec 16^th, 2017, 11:01pm

My main issues is that when I use transmission gates in cmos for the switches I do not get the SNDR i want - should i use another form of switch like bootstrapped switches for the switches instead?