Problems with Hspice regarding transient analysis of PLL

[analog_up]

Dear all,
I encountered two problems when using Hspice, and have no idea with the causes.
1、There are some warnings : resistance is negative, it may cause instability problem. I wonder what this warning means, how it comes, and how to clear it.
2、When doing transient analysis of PLL, a run-time error occurs,as showed in the attachment. I don't know where to locate the problem.
So, would you please give some advices, thanks.

 

[mpig09]

Re: Problems with Hspice

Dear analog_up :

Please use other HD to simulate your PLL.


mpig

 

[analog_up]

Re: Problems with Hspice

HD? You mean change to another machine for simulation?

 

[Material]

Re: Problems with Hspice

I have met error like this.
Check your netlist, there may be some errors.

 

[analog_up]

Re: Problems with Hspice

Thanks for all your advices.
I have solved problem 2 by setting OPTION gmindc to a bigger value 1e-10. But I still wonder what the real problem is. Can anybody give explanation? Thanks

 

[mkhafaji]

Problems with Hspice

sometims when you choose very low values HSPICE convergence problems happend and some values in its iterations went out of its precision and run time error is shown

 

[mpig09]

Re: Problems with Hspice

HD? You mean change to another machine for simulation?

Yes!!