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Simulators >> Circuit Simulators >> PSS for characterising switch mode amplifiers?
https://designers-guide.org/forum/YaBB.pl?num=1188210085

Message started by Prabhu on Aug 27^th, 2007, 3:21am

Title: PSS for characterising switch mode amplifiers?
Post by Prabhu on Aug 27^th, 2007, 3:21am

Is PSS analysis suitable for analysing switch mode amplifiers like class D PAs?

Thanks,
Raja

Title: Re: PSS for characterising switch mode amplifiers?
Post by Ken Kundert on Aug 27^th, 2007, 10:03am

PSS and its small-signal minion (PAC, PXF, PSTB, etc) can be used on switching amplifiers as well as switching regulators. PAC & PXF can be used to find things like small-signal output impedance and supply rejection. PSTB can be used to measure the loop gain of the amplifier. PNoise can be used to determine the noise performance. One can also use QPSS to measure distortion and Envelope Following to speed up a long transient analysis.

What is it that you are trying to measure?

-Ken

Title: Re: PSS for characterising switch mode amplifiers?
Post by Prabhu on Aug 28^th, 2007, 3:03am

Thanks for the reply Ken.
I need to characterise the distortion and stability performance of a switching (pwm) amplifier in feedback.
I was not sure whether to use PSS since it is not recommended for a similar delta-sigma modulator system.

Raja

Title: Re: PSS for characterising switch mode amplifiers?
Post by Ken Kundert on Aug 28^th, 2007, 2:04pm

A prerequisite for use of PSS is that your circuit have a periodic solution. Sigma-Delta converters do not have periodic solutions. If your amplifier uses delta-sigma modulation then you probably cannot use PSS.

For stability use PSS/PSTB. For distortion use QPSS/QPAC.

-Ken