gate current in a HEMT

Thread Starter


Joined Mar 17, 2022
Hello, I'm trying to understand the use of a HEMT as a power amplifier. I want to design a driver for a power amplifier and so I need to deliver enough current to charge the gate capacitance. I wanted to know if there is any other current I should take into consideration.

For instance, the gate contact is a Schottky one, if forward biased, it will "absorb" some current. How can I know how much current it would absorb?

I've also found this graph ( source : Reliability modeling of high voltage AlGaN/GaN and GaAs field-effect transistors)

why is there this decrease in the current close to 14dBm before it increases? What could be the physical explanation for that?

And last, I will be biasing my gate with a DC voltage and once the HEMT is on, the RF signal will be introduced. Will it affect the gate current in some way?

Thank you in advance


Joined Oct 7, 2019
I think you are making a linear RF amplifier??
What part number?

I use GaN transistors in power supplies where the parts are full on or off and never in the linear region, so I might not be much help.