How can I accelerate the PSS simulation of VCO?

[Patrick520]

Hi
I am design a vco for zigbee receiver, whose oscillating frequency is 2.4GHz.
In Spectre ADE, I choose the PSS (shooting) simulation.
But I find that simulation speed is too slow.

The simulating netlist presents as:
pss: time=13.19us (3.23 m%), step=1.839ps ( 200 p%)
pss: time=13.26us (3.25 m%), step=2.38 ps (400 p%)
.......

My question is how can I accelerate the speed of PSS simulation?
The step is too slow like only 1.839ps.

How can I set the PSS parameter?

 

[BigBoss]

There might be some model problems as well as convergence difficulties.
Did you insert a settling time for your VCO to pass the initial period ? You may also loosen the tolerances..
In fact, there are many tricks for convergence problems but every problem has its own trick therefore saying something for a particular design is not easy..