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AN1317 - APPLICATION NOTE

device). This situation is due to the fact that the minimum turn on of the device is not sufficiently short to

keep the drain current under control, especially because the inductor is saturated.

Nevertheless, the device is protected against such events and can be connected directly across the front

bulk capacitor charged at 400 V without any problem. This corresponds to the worst case of a saturated

transformer, which is never reached practically. Would it happen, the resulting power dissipation would

be limited by the thermal shutdown of the device.