Re: Operating temperature derating

On Mon, 3 Jun 2024 07:52:58 -0700, Don Y <blockedofcourse@foo.invalid>
wrote:

Presumably, one should feel comfortable using a device at the
published operating temperature extremes "forever".
>
But, what sort of derating likely went into that specification
in the first place?  Sad another way, how much *beyond* those
limits might want suspect you could operate the device?

There are two basic limits to operating environment temperatures.

Junction temperature limits are usually proscribed below book
Tjmax for an agreed mtbf. Sometimes the environmental limits
can be extended under reduced performance guidelines, without
exceeding agreed Tj limits.

For a whole product, there's usually other component limiting factors
that occur first - electrolytic and film capacitors, insulation system
ratings and surface touch restrictions.

Performance is measured with these specified limits in mind.

or not.

RL