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[email protected] antispam@math.uni.wroc.pl is offline
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Default another dimmer smoked today outside thank goodness!

Phil Allison wrote:
wrote:

=============================

** Some uni****** dope


A device like that needs a proper heatsink. Even if the metal tab is soldered to the PC it's
still inadequate for high power applications.

For 70A mosfet 7A is light load. Estimate based on typical
values shows that it should disspate about 0.3W.


** It will be much higher in practice.


to handle nominal 30A, than heatsink would be necessary.


** The OP's rms current is way higher than 7A.

The above assumed that there is an inductor and that second
HY1707 works as synchronous rectifier.


** You on crack ???

Do you have no idea what this device is ?

It is **NOT** a power supply .

It is just an on/off switch performing PWM lamp control.


Well, I would prefer to put inductor in such device. But
you are right, inductor (+ good control) would be too expensive
for current market. At first I was mislead by mention of two
mosfets, but connecting them in parallel (to get higher current)
in simple PWM makes sense.

--
Waldek Hebisch