PSS not converge in a receiver simulation.

[zxmung]

Hi there,

Ive built a LNA + Mixer + Lo direct down-conversion receiver. flo = frf = 5.2G. However I met lots of trouble when trying to get IP3 and Noise Figure of total circuit.

Cadence cannot perform pss simulation due to non-convergence. At first it's because we have both driving source and autonomous in one circuit. So I add a small source current into LO so that the entire circuit is not autonomous, and add long tstab (30n). But it still doesn't work.:-(

Any comments?

 

[tony_lth]

Your LO and RF should be at least several ten Hz different

 

[BigBoss]

You can not simulate whole receiver chain with PSS. At least, there is a VCO and its frequency is not know therefore PSS common beat can not be defined.Since the common beat is not defined, PSS will never converge.