EEVblog 1461 - The MOSFET Search CHALLENGE

[EEVblog]

Join Dave in the search for an alternative replacement MOSFET. It might not be as easy as it sounds.
Talk about how to identify components and function, MOSFET parameters, and using google and parametric searches on supplier and manufacturer websites.

[BrianHG]

Aren't the Gate protection diodes Zener, not Schottky?

[EEVblog]

Aren't the Gate protection diodes Zener, not Schottky?

Yes, zener, did I say schottky?

[BrianHG]

Aren't the Gate protection diodes Zener, not Schottky?

Yes, zener, did I say schottky?

Not only did you say anti-static schottky, you insisted every step in the entire video as well as searched for schottky protected mosfet.  Guess what all your schottky protected mosfet results were:  An extra protection schottky power diode between the drain and source.

[BrianHG]

@39:00 My mistake, you were looking for ESD protected gate, but that made me more attentive throughout the rest of the video as I've knew about Zener protected gate, but it was the first time I heard someone calling it ESD like you see in IC inputs.  You never specifically said you should search for schottky diode protected, but you kept on bumping into it in your search results.

Equivalent Protected Gate at Digikey with stock:
FDS7779Z                     Near perfect choice.
SQ4483BEEY-T1_GE3  Double protected Gate with series resistor special.

Others without stock at Digikey.
SI4491EDY-T1-GE3     Stock at Mouser and Arrow.
AO4447A                     Stock at Bristol Electronics.
FDS6681Z                  Stock at Mouser.

Others exists, but their good VGS on voltage begins at -10v, not -4.5v, so you need to be careful there.

Also remember, when a MCU manually drives a P-Mosfet's Gate, it may be done with a open-collector IO pin or NPN transistor collector output through a series resistor.  If you power supply is 2x8v batteries in series, potentially above 16v, those protection diodes may be in use to prevent the gate from exceeding a maximum -15v, or -12v for low gate voltage mosfets.

[tinfever]

AO4425 is in-stock on Digikey...barely. The Octopart stock history chart is kind of scary for that.

Interestingly, AO4425 has an ESD rating of 4kV HBM, the Vishay SI4491EDY also is rated for 4kV HBM, and the Vishay SQ4483BEEY is only rated for 3kV. The original SM4303PSK has an ESD rating of 8kV HBM. Are there some applications when that rating difference would matter?