LMG1210EVM-012: Heating Issue with LMG1210

Hello Farhan,

What device or devices on the board are heating up? What is the temperature?

This device has a maximum recommended junction temperature of 125C. Is this being exceeded?

Please try the calculator on this FAQ for the maximum switching frequency based on the driver, FETs, and Vin.

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1025075/faq-ucc27282-how-to-calculate-the-max-operating-frequency-of-a-half-bridge-gate-driver

Thanks,

Walter

Hello Walter.

Thanks for reply. LMG1210 IC is heating up .I don't know the exact temperature but if I can run it for few minutes its heat a lot .so I cant even touch it and current also increase continuously .Can you please once review the design file  and guide me if i did any mistake. Thanks

Farhan

Hello Farhan,

Are you testing the board at room temperature 25C? With a 5MHz switching frequency, the part might theoretically heat up to around 75C.

Is the output to the FETs normal? If the thermal shutdown is triggering I suggest adding a heatsink if possible.

I do not see anything too abnormal with the design.

Thanks,

Walter

Hello Walter.

Thank you for your response. Yes, I am testing the circuit at room temperature. I have attached the output waveforms of the LMG1210 at the high and low output pins (pins 10 and 8).

I have selected a maximum dead time of 20 ns. However, if you look closely at the attached figure, there is a point where both outputs are slightly high simultaneously. Could this be the cause of the heating issue?

Secondly, right now I am testing at 10Vdc and 500mA but in real application i have to operate at 160vdc and 6A  that time there will be more heat? And while testing as long as temperature is increased the current is also increasing.

When the thermal shutdown is triggering the device will be damaged or shutdown?

Thanks

Best Regards

Farhan

Hello Walter,

Thank you for your response. I selected a maximum deadtime of 20 ns using a 20 kΩ resistor, but I'm still seeing around 3 ns of overlap. I also checked the temperature of the LMG1210, and it was around 85°C at a switching frequency of 3.2 MHz. I will test it at 5 MHz as well. Do you think this temperature is within the normal range? Can you recommend  heatsink or cooling material for Lmg1210 and GaN FETs . Thanks

Best Regards

Farhan