Have P-channel Depletion mode MOSFETs ever existed in real life?

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gbugh

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I see electronics educational articles and trade magazine articles about P-channel Depletion mode JFETs and MOSFETs and I even thought I had once created a list of available part numbers but now my list disappeared and I can find none available anywhere. Are they simply theoretically possible but no manufacturer has ever made any? Now I find depletion mode only available in N-channel MOSFETs. If no one ever produced them, why not? Low demand? UPDATE: Actually, it seems like I can find them but only if the word "depletion" is not on their datasheet. Like this one: https://www.digikey.com/en/products/detail/onsemi/j174/1050079 The J174 in a P channel and it has max current at 0V gate bias but the datasheet doesn't say depletion anywhere. This makes it seem like all P channel depletion mode have been searched for and removed from the internet. But if those deleting them failed to find them with a search for "depletion" and "P channel" then they might still be on the internet somewhere. This is very strange??????

Like this is still findable because it doesn't mention "depletion mode" and "P channel" (as text words) together anywhere:
AskElectronics/comments/1103qlh/j174_pchannel_fet_not_turning_off_led_while_gate
They are only mentioned together as part of a graphic image.
 
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Even 40 years ago depletion-mode JFETs seemed getting phased out. I bought three 2N3819 (N-channel) in a package somewhere (maybe Radio Shack). From a mail-order house I bought three P-channel.

To use a jfet is unintuitive. Turning it off requires voltage beyond the range of supply rails. Reversing its direction doesn't change operation. However reverse polarity on the bias terminal is bad for it.

Despite its high bias resistance I've only seen it in a few places. FET-vom. FET-input-opamp (TLO-81 family). OTOH enhancement-mode mosfets are easier to understand and obtain.
 

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All JFETs are depletion mode, you are however asking about MOSFET.
You probably know there's a small portfolio of NMOS depletion types available, but apparently no PMOS depletion transistors on the market. Technically, it's not impossible to make depletion mode PMOS transistors according to literature, but there seems to be no commercial application for it.

 

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I have worked in one technology which had for each {N,P} had 4 different VTs made by crossing up 2 implant doses and the gate poly shot (this, distinct from the S, D implants).

"I" and "D" versions were there. The DP device worked well; the DN needed way more than min L to "look right". I used them for sleazy no-bias cascodes and startups.

You might find depletion MOS discretes in the RF segment, though who does RF using P devices, really?
 

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