peter green wrote:

>> You cannot simply create a voltage which is 12V above your supply rail
>> and feed that to your high-side fet gates (at least not without a
>> zener clamp on each one). This is because initially, when the source
>> of the high side fet is at 0V, applying Vsupply+12 to the gate would
>> cause Vsupply+12 of gate-source voltage on the high-side fets. This
>> would only be for perhaps 100 nanoseconds or so, but could be enough
>> to punch through the ultra-thin gate oxide layer (due to violation of
>> Vgs_max spec).

> can't you just select fets that are suitable for a gate source voltage of
> vsupply+12

If you can :)

Most MOSFETs are limited to a Vgs of 20V or lower, so there's not that much
of a variety here if you'd need more than that.

Gerhard

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