Vasile Surducan <piclist9 <at> gmail.com> writes:

> AFIK, there are some issues on fast triac switching like dv/dt which
> could turn on the triac without any gate command. So the load
> characteristics it's important (it's resistive or inductive?). 

I thought about dV/dt but my dV/dt is not so terribly high. The input is a
reasonably almost-sine wave from a dc/dc converter through a simple filter.
 
> The question is why use triac at 50V and 50KHz switching (assuming
> you're not switching 100 A) ?  The reason of using a triac is
> automatic turn off at lowest A1-A2 current than holding current and
> bidirectional current conducting.
> Using two MOS FET's will do the probably same like a triac without
> those problems.

I need to switch about 8 Aeff. So the peaks could be 100A at least temporarily.

Using 2 inexpensive mosfets 'back to back' is possible but I don't like what I
need to do to drive the gates (the gates float on the 50kHz - it is a high side
switch). That is: I know precisely what I need to do to drive the gates and I
have done it before, but I would like something less sensitive (than mosfets) as
a switch there.

Peter P.


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