did I get faulty amplifier question

[yefj]

Hello, I have bought an amplifier shown below.However when I am trying to test if my VDD is shorted to GND my measuring i get the DMM beeping as if the VDD is shorted to GND. ash shown in the layout below
Also when I measied the resistance across C2 capacitor I see only 1.6ohm.
DId I get a faulty component?
Thanks.
A video of me doing the test is attached in the link.
Thanks.

https://www.minicircuits.com/pcb/98-pl771.pdf

SMT MMIC, High Power, Linear Amplifier, 10 MHz to 10 GHz, 50Ω, 5x5 mm QFN Style Package | PMA5-83-2W+ | Mini-Circuits

Mini-Circuits is a global leader in the design and manufacturing of RF, IF, and microwave components from DC to 86GHz.

www.minicircuits.com

20250508_115940000_iOS.MOV

 

[FvM]

GaN transistor are depletion mode type, low-ohmic drain source without negative gate bias. I don't know if the amplifier is healthy, but similar measurement results are expextable.

 

[mtwieg]

You must be very careful to sequence the bias voltages correctly, otherwise you will likely destroy it immediately. Read all documentation, twice.

There are two "gate" voltages you need to apply, Vg1 and Vg2. Vg1 is supposed to be -0.8V. Interestingly, Vg2 is positive, between +5-7V.

 

[yefj]

why my DMM says that VDD is shorted to ground?

 

[volker@muehlhaus]

Maybe one trivial aspect:
The amplifier seems to be delivered as SMD component, who soldered that to the PCB? Something wrong with soldering?

 

[vfone]

This is a GaAs device and not GaN.
But either of them require a bias sequence:

https://www.sedi.co.jp/pdf/application.pdf

If you don't follow this bias sequence the device dies instantly.

 

[yefj]

Hello ,I have built a biasing sequencer for this circuit, the sequence is displayed in the scope photo below.
do you think this sequence will work properly for the amplifier ?
It wont get burnt when the following sequence will be connected to it?
Thanks.