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Simulators >> Circuit Simulators >> why ac=1(magnitude) while doing ac simulation?
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Message started by somisetty on Mar 17^th, 2010, 9:38pm

Title: why ac=1(magnitude) while doing ac simulation?
Post by somisetty on Mar 17^th, 2010, 9:38pm

Hi,

would you pls let me know why ac=1(magnitude) while doing ac simulation?

THanks

Title: Re: why ac=1(magnitude) while doing ac simulation?
Post by yvkrishna on Mar 17^th, 2010, 10:08pm

no special reason for it, just a matter of convenience , you can see the gain directly by plotting the output voltage.

regards,
Vamshi

Title: Re: why ac=1(magnitude) while doing ac simulation?
Post by Andrew Beckett on Mar 18^th, 2010, 4:03pm

Essentially if you're doing a linear small signal analysis, it doesn't matter what magnitude the input signal is - the gains will always be the same.

You could choose to put a realistic signal magnitude at the input, and then you'll get a realistic signal at the output, and could then calculate the gain by dividing the output signal by the input signal. By setting the input signal to 1, you directly get the gain (from the input source) at the node you plot.

Regards,

Andrew.