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AC switching mos-fets

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Lusu:
BTW... the chip has Miller clamps built in... isn't that what a snubbler does anyway?

From datasheet, 2.6.1  Miller Clamp Description:

"The Si875x devices provide a clamping device to prevent unintended turn on of the external FET when a high dV/dt is present on the FET’s drain. To use this feature, a capacitor is connected between the drain(s) of the FET(s) and one of the MCAPx inputs. A sudden, positive slope on this pin will cause the clamp device within the Si875x to activate and provide a low impedance path between the gate and source pins. This will prevent the FET from being unintentionally turned on.
The Si875x device provides two miller clamp input pins. This allows for both FET’s to be protected from unintended turn on when the device is used in an AC switch configuration. In this case each drain is connected to an MCAPx input through a capacitor.
Connection to a MCAPx pin, and use of the Miller Clamp feature, is optional. The device will function as expected if these pins are left unconnected."

I guess that for LED bulbs I need the snubbler, because classic (and halogen I belive) are resistive.

Jeroen3:
The snubber takes care of the voltage transient that occurs when you turn something off. It has not much to do with the gate directly.
It just prevents Vds going over maximum rating due to inductive loads.

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