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I am putting surface mounted resistors inside a vacuum chamber and then baking the vacuum chamber at 200°C for 2 weeks, no voltage will be applied to the resistors during this time. Will this damage the resistors if they are rated up to 155°C?

JYelton
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fgsiv
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  • What resistors they are, do they have a data sheet? – Justme Jul 17 '23 at 15:24
  • Here is the data sheet: https://www.digikey.com/en/products/detail/koa-speer-electronics-inc/WK73R1JTTD102J/10274596 – fgsiv Jul 17 '23 at 15:34
  • The issue is the size, high temp resistors are normally very large. We are looking for something that is round 1 mm long and .5 wide. – fgsiv Jul 17 '23 at 15:34

2 Answers2

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Without careful testing, there is essentially no way to know.

There are resistors out there rated for the temperature you're using it at. For example, THESE at Digikey. If it's important that your device works when it's powered up, I recommend using a high-temp option.

Scott Seidman
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    Was just typing out an answer with words to this affect. These components are normally only designed to withstand these temperatures temporarily while they are being soldered. 2 Weeks would be an eternity compared to the few minutes they get whilst being reflow soldered. – Entropy Jul 17 '23 at 15:17
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It depends on a few things. You should not go above the storage or operating temperature in the data sheet. so if it's 155C for a Max temperature then it's likely that you'll damage them at 200C.

Most smt components can tolerate more than the operating or storage temperature but only for a short time. They will specify this time in a reflow profile or specific the spec for the reflow profile.

If your resistors don't tolerate 200C get resistors that will.

Voltage Spike
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