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Max pressure for electronics (deepwater, downhole)?

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sicco:
I’m designing downhole electronics with Hall and other sensors such as ST MEMS accelerometers, magnetometers like ISM303DAC, LIS2MDL, Infineon TLE4968, TLE5012B. These automotive sensor chips in their LGA12, SOT23, SOIC-8 or PG-SSO-3-2 packages have the temperature spec that works for me (150 C ish). But the application will expose the packages, likely submerged in oil,  to pressures into the 100rds of Bars (5000, 10000, maybe 15000 psi).
Not one single datasheet that i could find says anything on max outside pressure before such sensors in their epoxy housings stop working, or lose spec, recoverable or irrecoverable.

Anyone any experience on how much pressure before this stuff breaks?
I fear that approaching ST, Infineon, NXP or TI, ADI field application engineers / sales channels will not get me anywhere, so asking it here now.

voltsandjolts:
The electronics must not be exposed to pressure, that would quickly destroy your circuits.
Pressure is your mechanical engineer's problem ;D
For wires that need to enter the pressure housing you need to use pressure feedthroughs (Kemlon, Greene Tweed etc.)

mag_therm:
This is another case I have seen before on eevblog of designers reluctant to contact vendor applications engineers with queries on products they intend to use.
Why is that?
In my day and up to retirement recently they were  #1 contact

There are lots of electronic systems down boreholes and undersea, and of course it has to be done with the right parts and methods.

sicco:

--- Quote from: voltsandjolts on August 13, 2022, 07:39:11 pm ---The electronics must not be exposed to pressure, that would quickly destroy your circuits.
Pressure is your mechanical engineer's problem ;D
For wires that need to enter the pressure housing you need to use pressure feedthroughs (Kemlon, Greene Tweed etc.)

--- End quote ---
What i have is a spinning shaft driven by a BLDC motor. The motor with Hall sensors is a Maxon catalog item, and claimed to survive the targeted high P high T when oil immersed. All drive electronics is in a pressure isolated atmospheric chamber, with the high pressure feedthroughs that you mention. The motor shaft and thus the motor is directly exposed to fluid, at high pressure, because it must interact with that fluid. I need a few more Hall position and orientation sensors, plus some magnetic sensor coils with sensor chips. Those sense something in the fluid. And those will be directly exposed to the high pressure.

The 3 Hall sensors inside the Maxon BLDC oil&gas, geothermal well ‘catalog’ assembly somehow can survive high pressure exposures. So what i want to learn now is what to do with mass market automotive style Hall and MEMS etc sensors to make them also survive downhole. Embed into glass maybe? Or just use the naked epoxy package and keep fingers crossed? Pot into another layer of epoxy?

sicco:

--- Quote from: mag_therm on August 13, 2022, 07:55:43 pm ---This is another case I have seen before on eevblog of designers reluctant to contact vendor applications engineers with queries on products they intend to use.
Why is that?
In my day and up to retirement recently they were  #1 contact

There are lots of electronic systems down boreholes and undersea, and of course it has to be done with the right parts and methods.

--- End quote ---
When did you retire then?

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