A pretty "cool" board, this Portenta H7 MCU module. Fully packed with a lot of chips and features.
I was a bit skeptical about heat generation (dissipation) when I use many features at the same time and full speed running all in parallel.
So, I run my FW with:
ETH (network traffic), USB-C for UART messages, run SDRAM test - in parallel
(not used: WiFi/BT, QSPI flash, Crypto chip).
Here the results (thermal camera picture, taken with a human body scan camera, therefore hot is out of range):
BTW:
This is WITH a (passive) heat sink on MCU chip already.
My conclusions:
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it should "survive" my use case (using heat sink on MCU and with the breakout board) - MCU might reach 55C (OK, rated for ambient 85C), I need just Power (PMIC), USB-C, ETH, SDRAM, MCU
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heat travels a bit also to breakout board (with large thermal resistance), potentially via high-density connectors and infrared radiation) - assume: breakout board does not contribute really for cooling so much. But it gets warmer as well (maybe +5..10C above ambient temperature).
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if you use the Portenta H7 MCU module itself (without heat sink, without breakout board) and using all the features (ok: ETH not usable, but also with WiFi/BT and QSPI, Crypto) - the board temperature could reach 60C, the MCU maybe 70C - but still OK (85C rated as all the other chips should be, at least 80C).
Improve Cooling
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place a (passive) heat sink on MCU chip (might help for -10C lower)
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if you can: solder the headers left and right: even not used - they provide additional cooling (for the entire board)
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the PMIC (power controller IC, the most second hot chip) and ETH controller (the hottest chip on board), USB-C chip - are too tiny in order to provide a heat sink for those. WIFi/BT plus SDRAM plus QSPI flash - maybe a shared heat sink possible
Anyway. I am a bit surprised (in a positive way):
I was expecting much more dramatic temperatures on this tiny board. But it looks OK.
Just: if I run the board all the time with 70C on MCU, maybe entire board with 60C (and even all not used chips are heated up to 60C) - the life span might degrade a bit.
With full load - you can burn your fingers on MCU chip (I can touch with heat sink barely). If you place this board in enclosure - make sure to have a proper (passive or even active) ventilation.
But OK, I am fine with the thermal analysis. Pretty "cool" board.
