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High GBW jelly bean transistor

Started by David Eather September 23, 2011
Does anyone have a suggestion for a transistor (npn pref) that has a 
higher GBW than a BC547 or 2N2222 at 2 - 10 ma?
On Fri, 23 Sep 2011 14:14:05 +1000, David Eather <eather@tpg.com.au>
wrote:

>Does anyone have a suggestion for a transistor (npn pref) that has a >higher GBW than a BC547 or 2N2222 at 2 - 10 ma?
BFT25 is 5 GHz. Nice part. Interesting DC behavior, too: it makes a superb low-leakage diode. BFS17 is only 1 GHz, but that can often be an advantage over something faster. It behaves itself pretty well. John
On Sep 23, 6:14=A0am, David Eather <eat...@tpg.com.au> wrote:
> Does anyone have a suggestion for a transistor (npn pref) that has a > higher GBW than a BC547 or 2N2222 at 2 - 10 ma?
My broad-band jelly-beans are the 5GHz NPN BFR92 and the PNP BFT93. I've never been able to keep them stable without a base-stopping resistor - someting like 22R in 0805 or smaller right up against the base pin - but with that addition they become very tractable. -- Bill Sloman, Nijmegen
On Sep 22, 9:14=A0pm, David Eather <eat...@tpg.com.au> wrote:
> Does anyone have a suggestion for a transistor (npn pref) that has a > higher GBW than a BC547 or 2N2222 at 2 - 10 ma?
You don't say how much more BW you need, nor what the voltage limits are, nor minimum beta...If you just need a bit more BW, and not too much voltage the 2N5769 (aka 2N2369) family might work.
On 23/09/2011 2:14 PM, David Eather wrote:
> Does anyone have a suggestion for a transistor (npn pref) that has a > higher GBW than a BC547 or 2N2222 at 2 - 10 ma?
Many thanks. have plenty to look at
David Eather wrote:
> On 23/09/2011 2:14 PM, David Eather wrote: >> Does anyone have a suggestion for a transistor (npn pref) that has a >> higher GBW than a BC547 or 2N2222 at 2 - 10 ma? > > Many thanks. have plenty to look at
A word of caution: The hfe of RF transistors is generally lower than that of a BC547. -- Regards, Joerg http://www.analogconsultants.com/
On Sep 22, 9:14=A0pm, David Eather <eat...@tpg.com.au> wrote:
> Does anyone have a suggestion for a transistor (npn pref) that has a > higher GBW than a BC547 or 2N2222 at 2 - 10 ma?
apparently you meant f cutoff 2N5088 has higher GBW than 2N2222 (I think) at least the G is higher SMT part numbers are different.
On 24/09/2011 7:34 AM, Joerg wrote:
> David Eather wrote: >> On 23/09/2011 2:14 PM, David Eather wrote: >>> Does anyone have a suggestion for a transistor (npn pref) that has a >>> higher GBW than a BC547 or 2N2222 at 2 - 10 ma? >> >> Many thanks. have plenty to look at > > > A word of caution: The hfe of RF transistors is generally lower than > that of a BC547. >
that's OK. I'm just playing with a couple of home/hobby designs.
2N5770 are a  nickel part with decent beta and GBW something a little
over a gig.

Jim

On Fri, 23 Sep 2011 14:14:05 +1000, David Eather <eather@tpg.com.au>
wrote:

>Does anyone have a suggestion for a transistor (npn pref) that has a >higher GBW than a BC547 or 2N2222 at 2 - 10 ma?
RST Engineering wrote:
> 2N5770 are a nickel part with decent beta and GBW something a little > over a gig. >
Looks like those are headed towards "geriatronics". Even Digikey says "Part will become a non-stocking item when stock is depleted". [...] -- Regards, Joerg http://www.analogconsultants.com/