Am I supposed to make a symbol for this schematic I copied from datasheet?

[rf_practitioner]

I am looking at a data sheet for ATF55143 and there is a die model and a package model on pg 17. Am I supposed to create a symbol for the package model if I want to accurately create simulations using this particular pHEMT? Also, I can't seem to find any ready-made ADS models for e-pHEMT transistors. Is there an online resource, maybe a repository, that gives access to ads models that are compatible with ads 2020?

 

[rf_practitioner]

Hello, I am trying to use ATF55145 and have been stuck. The feedback i got said to copy the model from pg 17 of the datasheet and so i did that but i never had to do that before. am i supposed to convert this into a symbol or should i bias the circuit directly? When I embarked on making an LNA, the hope i had was that I could find a ready made model but that didn't work out. At this point, I'd be happy if I could convert this into a symbol and move forward by using the symbol as if it were a built in transistor and continue on with the biasing and so fourth requried for the rest of my LNA design.

 

[dick_freebird]

If you are working from a schematic capture GUI environment then the device model comes in through a symbol but this might just be a "generic" (NJFET, NMOSFET or if ADS is with-the-times maybe a purpose HEMT model of whatever morphic you like). The model would be called out by a symbol property (and given geom params most likely, check what those are in the top level netlist, a defaulted W and L may not play with a found model file).

The searchpath for models will be set at init file or explicitly in some menu fill form most likely. You must make the chain.

 

[johncaroline]

I am looking at a data sheet for ATF55143 and there is a die model and a package model on pg 17. Am I supposed to create a symbol for the package model if I want to accurately create simulations using this particular pHEMT? Also, I can't seem to find any ready-made ADS models for e-pHEMT transistors. Is there an online resource, maybe a repository, that gives access to ads models that are compatible with ads 2020?

Yes, if you're simulating the packaged device, use the package model to account for parasitics. For ADS models, check the manufacturer’s website or Keysight’s Modelithics library—sometimes they have pHEMT models. Also, RF forums and GitHub might have shared models compatible with ADS 2020.

 

[RealAEL]

Assuming that you have entered this schematic correctly, Ican only trust you on that, then ADS should do most of the work for you.

To make later step easy, however, I would exit your schematic so that the Gate pin was Num=2, the Gate pin was Num=1 and the two Source pins were Num=3 and Num=4.

Then use the Window menu in the schematic and select Symbol. The cell name offered should be the same name as the current schematic. Keep that and select Create Symbol. In the window that appears select the second Copy/Modify tab. From here there are many choices by the easiest method that lines up aas close as possible to your case would be to navigate to the "Devices - GaAs" category and select the EEFET3 symbol and select OK.

This should give you a 3-pin device. You will need to copy/paste the Source connection and pin3 to create the second source pin (pin 4). The results should look like this:

Final step is to save this symbol cellview and you should be ready to go placing this custom cell in a new schematicto create your design and perform simulations.

 

[ahsrabrifat]

I am looking at a data sheet for ATF55143 and there is a die model and a package model on pg 17. Am I supposed to create a symbol for the package model if I want to accurately create simulations using this particular pHEMT? Also, I can't seem to find any ready-made ADS models for e-pHEMT transistors. Is there an online resource, maybe a repository, that gives access to ads models that are compatible with ads 2020?

Yes. Specially if you want to print a PCB.