At what temperature will the pcb melt?

[unyalli]

I know they de-rate to 80 amps at 40c (104f) but what temperature is melt down?

- Jeff

[boB]

That's a good question !

The insides of the power FETs (the DIE) is good for peak temperature of  175 degrees C (347 F)
from its specifications and design but of course outside of that it has to be cooler.  There are
rules of thumb and then there are more accurate measurements that can translate to
maximum temperatures allowed by the rest of the components.

In general, the FET temperature you see on a Classic is desirable to be kept below 100 degrees C
or so but we try to keep it lower than 85C if possible by turning down the power (raising the
input voltage).

Now, the meltdown temperature of the PCB itself ?   I'm not sure really.  Very hot though.
They certainly can burn though if not careful !  That amount of power usually comes from
the battery though if a unit should cack. They can turn into burnt weenie sandwiches
(as Frank Zappa says) if the battery bank has its way with the copper on a PCB.

boB

[unyalli]

Thanks Bob, no worries at 45 C then.