Up to which altitude does the STM32 work properly?

[Daniel H]

Posted on February 14, 2018 at 08:35

I want to shoot it in about 20km altitude, but I have doubts about if the microcontroller still works under that low pressure. Does also anyone know the distance of the conducting paths?

#altitude

[AvaTar]

Posted on February 14, 2018 at 09:26

... but I have doubts about if the microcontroller still works under that low pressure.

That would be new to me.

Decreased atmospherical schielding will increase bit errors rates, though.

[Andrew Neil]

Posted on February 14, 2018 at 13:10

Does also anyone know the distance of the conducting paths?

Not clear what you're asking there?

This is not a PCB design forum ...

[henry.dick]

Posted on February 14, 2018 at 13:20

Try to figure out exactly what challenges high altitude poses poses to your chip: low temperature, low pressure, radiation, ionization, ..... And then recreate similar environment on the ground to test your chip.

[AvaTar]

Posted on February 14, 2018 at 13:50

Semiconductor components are usually hermetically sealed anyway, so there is no relation to the surrounding pressure.

Otherwise, your application is similar to automotive conditions (roughly -30°C ... +50°C ambient temperature) or aeronautics (elevations > 10km), so similar measures would apply.

My company casts outdoor machinery electronic equipment in non-foaming PU lacquer.

[Daniel H]

Posted on February 14, 2018 at 16:01

The device will be capsuled so temperature and radiation won't be a problem but I wonder if it survives the low pressure or will flash overs happen?

[STOne-32]

Posted on February 14, 2018 at 22:03

Dear

danield

H

For which application usage : Spatial , inside a Zeppelin , Météo balloon ? Our STM32 are not rad hard qualified.

At below -40deg C our flash and overall digital should work if you increase VDD at 3.3 Minimum. Avoid operating at 1.8V. As exemple

But if it is just for fun, I’m interested to know if you do such test for us and share with the community ..

Cheers,

STOne-

[Andrei Chichak]

Posted on February 14, 2018 at 21:23

Automotive temperature range is typically agreed to be -40C to 125C.

From first hand experience, -40C isn't the issue with automotives. Oil and batteries don't like getting cold, semiconductors, I've been told, just work better and better so they stop the testing at -40C.

[AVI-crak]

Posted on February 15, 2018 at 02:13

Low temperature, low blood pressure, and radiation are all not important at high altitude.

Static ionization is your worst enemy.The stm microprocessors are very delicate devices, they do not tolerate spark hits of 2 kilovolts. Static voltage is collected on the parts of the probe itself, after which a breakdown occurs (spark). One small splash - and all your electronics turns into ballast.You need to protect the input signals of your PCB, and also apply a double screen with a weak connection.And yes, this is not an exciting activity.

[T J]

Posted on February 15, 2018 at 03:28

I believe there will be no issue at high altitude except the Radiation as discussed.

to avoid issues with radiation, short tracks on the pcb, if you can afford it, use a 4/6 layer board use the out two layers as shield planes connected with say 1KR to the Ground terminal on the battery.

then use the 2/4 inner layers for routing, this will stop the radiation charging tracks.

otherwise a aluminum foil wrap around the whole unit, would be sufficient to stop all the radiation.

(connected by 1KR to the Ground terminal on the battery)

or a steel box except for the weight issue.