Dear Rakesh,

Hope you are well!

The one dB compression point is not equal Psat -1dB.

The saturation power is value where the pot power saturates to a specific value which is the value of the saturation point.

You may use a back off point which is lower than the Psat with a specific number of dBs such that

P back off = Psat - Lbo in dBs

Other wise if you want to use P1dB compression point you have to empirically find this relation.

Best wishes

Dear Rakesh Krishna Vs ,

I hope you are doing well, I suggest you check this attached file, hope it helps!

Regards,

Dibyajyoti

Thank you fro your reply Dr. Zekry. I am not sure if I can find out Pback off using cadence tools. In the PSS analysis this is the closest I can get to see the saturation of amplifier.

Any alternate cadence analysis/method that can provide me w/ this information is appreciated?

Dear Rakesh,

Is it a low frequency TIA?

If yes, I think you can run an AC simulation and use Cadence's calculator to measure the power of the TIA Vs. the frequency.

Hi Ahmed,

In AC simulation (which is linear in nature), the output load shows its effect on the output power of the amplifier. So the amount of Psat will be different at different loading conditions. Now doesnt a load that is broadband and also providing maximum power entail an additional simulation?

Please, check out the following steps it may help you to plot the power vs frequency:

1) Choose AC (another analysis) analysis and specify the target frequency range.

2) From ADE L window --> Outputs--> Setup.

3) From Setup window --> click on From Design -->In Schematic on input-power source -nv (output-load +ve) terminal and input-power source net.

4) Run the simulation.

5) Go to the cadence calculator--> and check "vf "--> then go to schematic and click on the input-power source (output-load) net--> it will appear on the calculator window--> save this by clicking on enter.

6) In the calculator check the "if" --> then go to the schematic and click on input-power source nv- terminal--> it will appear on the calculator window.

7) click on multiply--> you will notice the calculator has multiplied the voltage and the current of the -nv (output-load) (the power)--> then click on evaluate the power --> Now you have the plot of TIA's power Vs. the target frequency range.

All the best.

Dear Rakesh.

If you want to determine the saturation power then the easiest way to follow is to determine the input power range to always insure that the output power is is saturated. So, one easily runs the simulation at any point of the input at this range. In summary you make Pin >= Pi sat.

The other method to import the results to the Matlab and perform whats ever processing you need.

wish you success!

Best wishes

Please read my book

American University Laboratories for Electrical Engineering (part 2)

Please read my book

American University Laboratories for Electrical Engineering (part 3)

I hope you find a good answer.