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Simulators >> Circuit Simulators >> Paper-"A test bench for diff. circuits"
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Message started by svensl on Apr 16^th, 2005, 6:19am

Title: Paper-"A test bench for diff. circuits"
Post by svensl on Apr 16^th, 2005, 6:19am

I just had a look at the paper mentioned above and had a go at the test bench provided in Figure 6. When measuring the differential mode gain using an AC analysis I noticed that the roll-off of the gain occurs slightly earlier when compared to an ordinary test bench set up for diff.-mode gain, meaning that the UGF is lower. Am I doing something wrong? I am used to taking the dB20((vout+ - vout-)/(vin+ - vin-)).

Thanks.

Title: Re: Paper-"A test bench for diff. circuits&qu
Post by Ken Kundert on Apr 16^th, 2005, 8:11am

The test bench given in the paper allows you to simply and independently specify the differential and common-mode impedances seen by the circuit at both the input and output. The test bench traditionally used does not. If your circuit is behaving differently with the new test bench, it is probably because one of these impedances is different.

-Ken