switching circuit simulation in hspice

[MOHAMMAD ALEEM]

I want to simulate duty cycle resistor based amplifier using HSPICE . transient analysis results are fine but unable to get AC response of circuit. Can anyone help?

 

[KlausST]

Hi,

are you aware that we don´t see
* your circuit
* how you tried to simulate it
* the results
* the error description
* your expectation

Klaus

 

[MOHAMMAD ALEEM]

I am simulating a duty cycle resistor based neural amplifier . Duty cycle resistor basically have one switch of MOS and large resistor in kilo ohms. When the same circuit is simulated using simple resistor in place of duty cycle resistor then all results are fine for both AC analysis and trans analysis. But when duty cycle resistor is included then trans analysis gives perfect result but AC analysis curve is showing absurd result. There are previous very old threads where this same issue is faced for switch capacitor circuit and reason given is that due to unstable operating point condition it can only be done with CADENCE with spectre with periodic steady state(PSS) analysis . Is there any option to run same file for AC analysis with Hspice?

 

[FvM]

AC analysis of switching circuits like switched capacitor filters or switched mode power supplies requires an analysis mode like PAC (periodic AC) or PSS (periodic steady state) provided by Cadence Spectre or POP (periodic operation point analysis) in SIMPLIS. HSPICE doesn't offer a similar mode as far as I'm aware of. HSPICE HBAC analysis works similar, but it's dedicated to sinuisodal carrier frequencies with harmonics rather than rectangular switching signals.

 

[MOHAMMAD ALEEM]

AC analysis of switching circuits like switched capacitor filters or switched mode power supplies requires an analysis mode like PAC (periodic AC) or PSS (periodic steady state) provided by Cadence Spectre or POP (periodic operation point analysis) in SIMPLIS. HSPICE doesn't offer a similar mode as far as I'm aware of. HSPICE HBAC analysis works similar, but it's dedicated to sinuisodal carrier frequencies with harmonics rather than rectangular switching signals.

do you have idea of HSPICE RF version? As i dont have access to CADENCE .

 

[FvM]

Unfortunately I don't use HSPICE.