Nexperia

There are still lots of fast NPNs. Not so many fast PNPs or low noise jfets.

ON Semi has resuscitated a bunch of old Sanyo JFETs, e.g. the CPH3910. The title of fastest PNP in production has declined from 8 GHz to about

Still, those current mirrors are good enough for some interesting things if you apply a bandaid to equalize the dissipation and V_CE on both sides. Not as good as a CA3046, but what can you do?

Cheers

Phil Hobbs

Renesas/Intersil makes a high-speed 3046 and 3096 variant, NPN Ft of 8 GHz and PNP Ft of 5.5 GHz.

It isn't cheap and the CE voltage is pretty limited. but there's stock available and looks to be current production item.

But higher current? and not low input C?

George H.

The problem with the HFA parts is that their Rbb' is horrible--like 300 ohms. I've been round that mulberry bush, believe me.

Cheers

Phil Hobbs

The oldest NXP datasheet in my computer is labeled Philips and dated 1997. The oldest Infineon datasheet in labeled Siemens, the file is from a CD dated 1997, but there's a 5.91 mark on the datasheet. Octopart has both company's versions still well in stock. It doesn't appear anything old was recently picked up by anybody, sorry!

One of my hobbies is designing pulse generator output stages. I had a cool one that used an Infineon CLY2 mesfet. It was discontinued but Triquint picked it up. Then they discontinued it.

Then I had a great one with an HP Phemt. Then it was Agilent. Then it was Avago. Now it's gone. So are its fast SOT89 PNP drivers.

I am optimistic that the EPC GaN fets will be used in billions of cheap wall warts so they might keep making them for a while.