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Fast PNP?

Hi, all,

A couple of years ago the last mainstream maker (NXP) stopped making the last fast PNP--the 5-GHz BFT92--thus depriving some of us of valuable design space, e.g. for improving the transconductance of FET bootstraps by wrapping a much faster PNP around it.

A BF862 or CPH3910 with a BFT92 wraparound makes a 750-MHz FET with 10x the transconductance but about the same noise. Magic.

I have ~9k BFT92s in stock, so I'm set for anything I might want to do myself, but for customer designs it's more of a worry. Not too long ago, the NTE2403 was announced, but stock seems to be, *ahem*, thin.

I ran across this datasheet:

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, which is marked "preliminary" and dated 2021. It's apparently a closeish second source for the long lost Renesas/NEC 2SA1977, which was even faster than the BFT92 (8 GHz f_T).

Anybody know anything about this outfit? I've never heard of them.

Thanks

Phil Hobbs

Reply to
Phil Hobbs
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Here too:

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I've had to redesign a few products that used fast pnp's in SOT-89.

Reply to
jlarkin

Here's the output stage of our P400 pulse/delay generator, the one you have.

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It's packed with obsolete parts. I replaced it with the GaN fet mouse-bite thing for the next generation.

Reply to
jlarkin

Yeah, there are a fair amount of NOS Renesas ones out there, apparently. For licensed designs it would be more comforting to be able to point to current production.

I have a reel of BFG31s too. (That's only a thousand pieces, of course.)

Cheers

Phil Hobbs

Reply to
Phil Hobbs

Nice gizmo, though.

Cheers

Phil Hobbs

Reply to
Phil Hobbs

Everybody should have one.

Reply to
John Larkin

Well I have heard of Unisonic and seen their parts in other gear but have no direct experience.

There is still the 2SA1669 at 3GHz?

piglet

Reply to
piglet

Just from brokers--no current production.

As I say, I have three reels of BFT92s, from which I can probably build $10M worth of TIAs if need be. (Just ask!) ;)

The issue is licensed designs, for which customers naturally ask questions about long term parts availability.

Maybe Unisonic will come through where NTE apparently whiffed.

Cheers

Phil Hobbs

Reply to
Phil Hobbs

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