Re: MOSFET answer

Hello Spehro,


Answering my own question about a TO-220 MOSFET that switches on solidly with 2.7 volts on the gate, the answer appears to be IRF3708.

This stuff is quite difficult to search. MOSFETs are one of those
components that's just exploding in options, and the parametric
searches often give you Rds(on) without telling you the Vgs for that
parameter. Many of the most attractive newer options (especially the
newer packages) turn out to be will-o'-the-wisp fata morgana parts
which are unavailable in small quantities.


It's also important to rely on guaranteed data and for Rdson at a certain Vgs that would be the "max" column. I have seen many designs where people just took the graph. Worked fine initially. Then another batch arrived and it was like popcorn.

Quite a few devices that are marketed as logic level are too marginal for my taste.

--
Regards, Joerg

http://www.analogconsultants.com
.

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