Testing to proove an SMPS over temperature

[eem2am]

Hello,

We have designed an offline SMPS.

Output is 50V and 4 Amps Max (200Watts)
Input is 85VAC to 265VAC

It is a boost PFC followed by a Buck.
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I want to test it at various temperatures from -10C to 80C.
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Muct i test it at lots of different load levels?
eg ...
20% load
40% load
60% load
80% load
100% load
....at each different temperature?

...at lots of different input voltage levels?
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or can i just check it on................

Minimum Line (85VAC) , Max Load at each temperature &
Minimum Line (85VAC) , Load switching from 0% to 100% at ~1 Hertz

Maximum Line (265VAC), Max load at each temperature &
Maximum Line (265VAC), Load switching from 0% to 100% at ~1 Hertz
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I had thought that the worst case for the feedback loop was minimum line and maximum load ?

...and basically if you have checked that there is no need to check at intermediate loads and lines (though of course max line must be checked)
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