zener diode protection.

[davepedals]

I'm sure it's been asked many times, I can't find the answer:
I know zeners are used gate to source for static protection, wouldn't gate to ground also work?
Thanks.

[Plexi]

I follow your doubt.
As I know, when they're with cathode to + (inverted), they mantain constant certain amount of voltage.
Each zener can mantain less than that voltage before "cut"...as a regulator.

[EBK]

What do you have against gate-to-source?   

[davepedals]

It's just simple curiosity!

[EBK]

The answer is probably, "it depends."

But, I'd prefer to think of it this way:
Imagine you are an unbelievably famous celebrity who needs to employ a bodyguard.  Would you be more comfortable if your bodyguard were always nearby, or would reachable-by-phone or just-around-the-block be ok?  Your answer may depend on how tough you are.  Well, MOSFET gates aren't tough.  They're quite delicate, actually.

Here's a better analogy:
Imagine the gate is a very thin and fragile window of a house, and to prevent differences in inside air pressure and outside air pressure (which varies with weather) from shattering the window, you have the ability to regulate the inside air pressure.  Would it be better to set it at a fixed amount or set it at an amount relative to the outside air pressure?

I feel like I'm channeling my inner Mark Hammer with these analogies (I hope I'm making him proud).   

[davepedals]

Good answer, gate-to-source it is then!

[Kipper4]

site search.


http://www.diystompboxes.com/smfforum/index.php?topic=100760.0

[davepedals]

Interesting read, thanks. My curiosity question has been answered.