p-channel depletion mosfets

At least there are p-channel JFET such as the MMBFJ175:

They're equivalent to NFETs for two-terminal use, of course. I'm not instantly thinking of a common three-terminal use for one, but I'm probably just dull this afternoon.

Cheers

Phil Hobbs

P.S.: There was the FJ3P02100L, a bigger p-channel depletion mode MOSFET from Panasonic but AFAIK it has been discontinued.

Are they physical possible?

Whoops, wrong FET. Can't find it anymore.

It seems so:

I'm sure they are; this one (zero-threshold) comes close.

but it's a very low-current solution.

P-doped material in Si has lower conductivity (lower carrier mobility) so there's not a lot of interest in discrete PMOS power devices. If my old handbook isn't wrong, AlSb has higher hole mobility than electron mobility... but no burgeoning technology around that semiconductor.

Joerg snipped-for-privacy@analogconsultants.com wrote: ...

No, NMOS logic use n-channel depletion mode!

I think the MC6800 and maybe 6802, pretty cool uPs in their day, used what was basically nmos RTL with depletion load pullups. The 6800 needed a weird 2-phase clock at 1 MHz.

I wrote an RTOS for the 6800, which was tricky because it couldn't push the index register onto the stack. And had no hardware multiply.

(I wrote it in ink on paper and mailed it a sheet at a time while visiting a friend in Juneau Alaska. People at work typed it on punchcards and assembled it and ran it. They claim that it had one bug.)