PA ADS simulation problem

[Boowei]

Hi to all
I did some PA simulation on ADS.as following.


I want to see Vin and Vout,but there is an error as the figure below after simulation.


and there is no problem when I simulate the S-parameters of the circuit as following.

what is wrong? who can help me? Thank in advance!

 

[ADS_RFMW]

HI

attach your ADS project file, so that we will help quickly.

 

[khouly]

i think u need to do decrease the time step in the trasient simulation

khouly

 

[aomeen]

Hello Kholy,

You mean increase...

The error message says it's too small...

 

[khouly]

i am so sorry , i miss understood the message

also boowie i don't recommend that u use s paramter in PA design , use LSSP , which Large signal S paramter , and also u need to use HB engine

try to post ur projct so we can check on it

khouly

 

[Boowei]

Here is my project.
I have change the time step,but it don't work

 

[khouly]

Dear boowie

i have check the image , u need to check the box , like the image

khouly

 

[BigBoss]

It's a typical convergence problem.There are something either in model files or "jumping" while transient simulation is running..

 

[asb1211]

For transient simulation, you must use a time step that is a multiple of the frequencies of interest or the results will not be correct.
Example:
To sample the fundamental (1900 MHz) plus harmonics, you must calculate @ 2 x (rate of highest harmonic desired).

1 / (2 x 15 x 1900MHz) = 17.54 picoseconds.

 

[zhlc3]

In your project, you set up the trans1/time setup/Min time step 0.1 picoseconds, this will bring convergence problem. let it be blank generally.

 

[Boowei]

Thank you! khouly . Your advice is ok.

Added after 6 minutes:

khouly How to use LSSP in ADS?

 

[khouly]

the LSSP , is like the HB

so insert the LSSP smiulator into the schematic , insert a power source and insert the termination for the load

adjust the Freq in the controller and here u go

khouly