STM32MP157AAD3 Heat dissipation

[Marudhupandian]

Why does the STM32MP157AAD3 have a higher heat or temperature? We have an STM32 board that has interfaces for PMIC, DDR3, temperature sensors, VOC, EMMC, LEDs, push buttons, WIFI+BLE modules, 8-pin connectors, wake-up switches are build in same board Sir, we have observed that the board can get as hot as 90 degrees Celsius when it is operating at full load. How can we deal with this heat problem? Could you please elaborate? I've included pictures of the board for your reference.

 

[PatrickF]

Hi,

there is no magic around thermal, as the board is small and you are using the smallest STM32MP15x package, the heat dissipation is limited.

Is the 90C a concern ? What is the Tj (could go up to 125C for STM32MP157A)?

Is the PCB has enough power plane for good overall heat dissipation ?

Did you check with thermal camera what are the main contributors of heat ?

Did you built some product thermal study or simulation ?

What is your overall consumption (board 5V or ideally split power per supply ) ?

Few tips to reduce overall dissipation:

- use DDR3L instead of DDR3 (if not already the case)

- avoid using DDR termination resistors (i.e. VTT) as optional for x16 DDR (if not already the case)

- check carefully if any power waste (i.e. reduce LDO input voltages when possible, etc...)

Apart SW mitigation (i.e. clock throttling when Tj exceed some limits), then you might need to add some mechanical/thermal connection to the board to help heat to go outside the board/case.

Regards.

[Marudhupandian]

Thank you for your valuable response....i will check and analyses you mentioned the issues...