Is it possible to design a HV CE amplifier that is robust with high gain using a bjt such as the 2N6517? I cannot get high gain and stay within spec for Vbe. I'm looking for a gain of about 10 with Vcc around 300V. I'll buffer the output if need be.
Thanks
What are you really trying to do? Your statements don't compute.
A voltage gain of 10 with a Vcc of around 300V should be a snap, with quite a few different parts including the 2N6517 (although you're not leaving yourself much safety margin with that part).
Did you mean HFE > 10? Is there a reason you can't use a Darlington connected pair? What current?
VBE (VEB?) is nearly immaterial -- design your amplifier so that the emitter never gets above the base, and you don't have a problem here. Did you mean VCE or VCB?
A two-minute search of the Digikey site coughed up the KSC5502. It has a VCE of 600V, and an HFE of 40 at 100mA. When you get the current up to the thing's rated 1A the HFE goes way down -- but there's no law that says you have to use it there.
define robust. define high gain define your specs for Vbe gain of 10 current or voltage, or hfe (not same if using an IF transformer) Give us a clue what you want and what the other unstated requirements are, maybe then someone can help
If you have a conflict between dc conditions and high gain, you can always use a dynamic Rc ie another transistor as a collector resistor.
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