How to use SpectreRF simulates Zin/Zout?

[feima87]

Dear all,
Is there anyone who knows the steps to simulate Zin/Zout in SpectreRF?
Many thanks!!!

 

[pancho_hideboo]

If you mean impedances based on small signal analysis, you don't need SpectreRF.
S-parameter analysis is a function of Spectre.

So run S-parameter analysis and calculate zm(1)/zm(2).

zm( x_index [?result s_resultName [?resultsDir t_resultsDir]] ) => o_waveform / nil

Description
Computes the port input impedance.
The zm function is computed in terms of the S-parameters and the reference impedance.

This function is a higher level wrapper for the OCEAN expression
(1 + s( x_index x_index )) / (1 - s( x_index x_index )) * zref( x_index )

This command should be run on the results of the Spectre sp (S-parameter) analysis.

Arguments
x_index Index of the port.
s_resultName Results from an analysis.When specified,
this argument will only be used internally and will not alter the current result which was set by the selectResult command.
The default is the current result selected with the selectResult command.
t_resultsDir Directory containing the PSF files (results).
If you supply this argument, you must also supply the resultName argument.
When specified, this argument will only be used internally and
will not alter the current results directory which was set by the
openResults command.
The default is the current results directory set by the openResults command.

Value Returned
o_waveform Waveform object representing the port input impedance.
nil Returns an error message and nil if there is a problem.

Example
plot(zm(2))

zm1 = zm(1 ?result "sp" ?resultsDir "./simResult/psf")
Returns input impedance at port 1 for results of S-parameter (sp) analysis stored at the location ./simResult/psf.

 

[feima87]

thank you,pancho!
you mean use sp analysis and calculate Zin by S11, right?
where can I find more about Zm command ?

 

[pancho_hideboo]

you mean use sp analysis and calculate Zin by S11, right?

Yes

where can I find more about Zm command ?

See **broken link removed**

 

[tdf]

Hi pancho_hideboo,

In the SP analysis of SpectreRF, it also calculate the Z11, Z22, etc..

Is that the Zin or Zout of the two ports circuit?

Thx,
tdf

 

[pancho_hideboo]

Is that the Zin or Zout of the two ports circuit?

I don't know what you mean by "that".

However Cadence ADE can calculate Zin and Zout from results of SP-analysis of Spectre not SpectreRF.

Surely read my appends in this thread.

Also read my appends in https://www.edaboard.com/threads/190077/

 

[volker_muehlhaus]

In the SP analysis of SpectreRF, it also calculate the Z11, Z22, etc..
Is that the Zin or Zout of the two ports circuit?

Z parameters are different from Zin/Zout.

Z parameters are defined with i=0 (open circuit) at the other ports.
Zin/Zout are usually measured with proper termination at the other ports.