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Noise analysis of PLL using HSPICE

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cmos_dude

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Hi All
Can anybody please guide me how to perform noise analysis of a PLL using HSPICE

Regards
CMOS DUDE
 

rfsystem

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Do want to model the PLL with AC response representing components or to simulate in the transient domain?
 

jlee

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I suggest to simulate the noise with cadence SPECTRE RF, instead of HSPICE.

Because PLL consists of VCO, which is a non-linear component. Frequency divider is also non-linear. For non-linear circuit, SPICE doesn't simulate well. Instead, you should run SPECTRE .pnoise analyse.
 

cmos_dude

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jlee said:
I suggest to simulate the noise with cadence SPECTRE RF, instead of HSPICE.

Because PLL consists of VCO, which is a non-linear component. Frequency divider is also non-linear. For non-linear circuit, SPICE doesn't simulate well. Instead, you should run SPECTRE .pnoise analyse.
I know that SPICE cannot predict noise directly in circuits having a quiescent operating point, like the PLL, but that is what I want to know wether there is some other way of doing the same using HSPICE.
I have a constraint of not having SPECTRE RF, which can directly run the PSS analysis, and am stuck to HSPICE only, so wanted to know if HSPICE also has some feature like PSS analysis.

Regards
CMOS DUDE
 

qslazio

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Firstly, PLL is a large mixed system. Hspice itself cannot afford such large amount of computation. You may wait several days to see the actual transient results.

You can use spectre (not RF)'s verilogAMS feature to see the noise effects on transient locking process.

If you really want to do analysis with Phase noise, you have to rely on Spectre RF, Hspice RF, Eldo RF or any other Hamonic-Balance Simulator to do Steady-State Simulation. As we know, phase noise itself is caused by non-linear of circuits. And hspice itself cannot afford that feature.
 

xwcwc1234

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What is the difference between Hspice and Hspice-RF ? I never heard Hspice-RF before.
 

dasong

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i have analysis the PLL's noise use Spetrice,someone tell me analysis the PLL's noise need the noise modol.
 

xwcwc1234

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noise simulation need device noise model, such as 1/f noise parameters in device model.
 

wjlzhx

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i alse have a problem,if i simulate noise ,should i add a source of noise.
 

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