Does anyone ever use enhancement-mode devices?

[keantoken]

I'm confused.

I've come up with a need for enhancement-mode MOSFETs in one of my circuits and I don't know if there would be any SPICE models for such devices. Since I've never thought about MOS/FET devices a second in my life I don't know how to go about this.

Are there any commonly used complementary low-current enhancement-mode MOSFETs suitable for an amplifier and are any SPICE models for these?

Thank you very much,
- keantoken

 

[juma]

You might search the net for:
- ZVP3306 or ZVP3310 / ZVN3306 or ZVN3310
- IRFD110 / IRFD9110
...
Google is your friend, don't be afraid to use it

 

[keantoken]

Well, now I have models. Thanks.

Why is it that I've never gotten .subckt models to work in LTSpice?

- keantoken

 

[thespeakerguy]

Do you mean depletion?

Most MOSFETs are enhancement devices. In the absence of a signal, the channel is off. It has been a while since I heard of a depletion mode MOSFET.

Most (all?) JFETs are depletion devices. They are on until they are turned off. In ICs, besides as JFET input amplifiers, JFETs are great to ensure circuit start up.

 

[keantoken]

Oh, thanks. I did mean depletion mode.

It doesn't really matter if it's MOSFET or FET, as long as it's depletion mode. I tried FETs though and couldn't get it to work...

Maybe I'll post the circuit.

- keantoken