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Simulators >> Circuit Simulators >> Methods to find ICMR of rail-to-rail amplifier
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Message started by Pooja on Mar 1^st, 2019, 5:31am

Title: Methods to find ICMR of rail-to-rail amplifier
Post by Pooja on Mar 1^st, 2019, 5:31am

Hello,
I have designed Rail-to-Rail amplifier. I have done DC simulation for ICMR using Voltage follower configuration. but as per my professor my output is limited , so i am not getting exact ICMR. Attached image has ICMR which i have got from DC Analysis.
Please, suggest me another methods to find out ICMR.

Title: Re: Methods to find ICMR of rail-to-rail amplifier
Post by Ken Kundert on Mar 2^nd, 2019, 10:25am

ICMR is input common mode range, no?

The way I would measure input common mode range is to sweep the input common mode voltage while performing a fixed-frequency AC analysis. The end of the range will be characterized by the drop in gain. The gain should be flat over the range and should drop off outside the range. If it is a DC coupled amplifier, I would set the frequency to 0.

-Ken

Title: Re: Methods to find ICMR of rail-to-rail amplifier
Post by Pooja on Mar 4^th, 2019, 8:30am

Thank you.