Is that test method okay?

When I'm doing a low temperature test, the output voltage sometimes goes higher than the set value or suddenly drops to 0V. . .
Can't you figure out what the cause is?

One possible cause of unstable output is the use of capacitors that are not compatible with low temperatures.

However, after checking the circuit diagram and parts list, there seems to be no problem with the selection of capacitors and other parts. . .

I don't know just by talking about it, so can you actually verify it?

I understand. I'll bring the equipment here, so please wait a moment.

(Huh???? Bringing it here, what kind of low temperature test is done???)

In the hands of the customer who returned was the evaluation board in question and a cooling spray. . .

I see...is that what you meant?

In fact, when performing low-temperature tests using cooling spray, the correct output may not be obtained.
If you are going to perform a low temperature test in the future, please check it in a constant temperature bath as much as possible.

Cause of abnormal output

It was caused by a low temperature test using a cooling spray.

Using a cooling spray can cause condensation around the device, which can increase leakage current between device pins and GND.

In this case, dew condensation occurred on the 8Pin Soft Start Pin and 6Pin COMP Pin, increasing the leakage current to GND, causing unstable operation such as the output voltage dropping/rising or dropping to 0V.

The point of this time

Low temperature test in a constant temperature bath!
Use of cooling spray causes trouble! !

application note

You can download an application note that introduces experimental results when using a cooling spray and how to avoid problems.