If you still want any good discrete analogue devices, this year is probably your last chance to buy lifetime stock.
No one is really doing well with analogue discretes.
NXP is sold / split, so discretes like BF862 are now Chinese.
Toshiba Semicon is most likely to be sold soon, and who knows what the new owner would do.
Fairchild is now On-Semi, so is Sanyo Semi, .....
The list keeps growing.
P.
No one is really doing well with analogue discretes.
NXP is sold / split, so discretes like BF862 are now Chinese.
Toshiba Semicon is most likely to be sold soon, and who knows what the new owner would do.
Fairchild is now On-Semi, so is Sanyo Semi, .....
The list keeps growing.
P.
I'm still frowning because of 2 external USB3 disk drives. 🙁
Did not last for one week.
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can the 3pin plug in be used to check the noise of BJT?
or does the Wurcer LNA only work for jFETs?
or does the Wurcer LNA only work for jFETs?
If you can find a way to supply the base current through the high-Z auto biasing circuit.
Patrick
Patrick
Good and good luck finding new choices. Even some batches of J310's were not too bad for some applications but nothing P made over the years by usual suspects ever was very good. Those P-channel switches National? made were OK but an unusual exception.
How about the PJFETs in the input stage of the TL072? Could a large area, basket weave layout on that fabrication process, give a low noise discrete if they wanted to try?
We still have a bunch of NOS P-JFETs for which we have no measured values.
e.g. 2SJ103, J174, ....
And I guess we can probably also measure MOSFETs if Vgs is <3V or so ?
Patrick
e.g. 2SJ103, J174, ....
And I guess we can probably also measure MOSFETs if Vgs is <3V or so ?
Patrick
Already did, gm/C figure of merit is not that good (50pF Cin for a 2.9nV diff-pair). On some of the new SOI processes things are better but no one is going to make discreet P FET's for fetish style design philosophies. Complimentary symmetry just sounds better, etc.
It appears that Mouser now carries affordable precision resistors, e.g.
http://www.mouser.ch/Passive-Compon...yzmq8c&Keyword=143195597&FS=True&Ntk=P_MarCom
Unfortunately, I could not find a 1R resistors in the series.
Regards,
Braca
http://www.mouser.ch/Passive-Compon...yzmq8c&Keyword=143195597&FS=True&Ntk=P_MarCom
Unfortunately, I could not find a 1R resistors in the series.
Regards,
Braca
Proto-board abuse 🙂 Everyone needs to learn how to design circuits that are immune to being made on these plug-in boards.
Ummmm... this could be "by design". I can't find the exact schematic, but the original Mr. Wurcer design in #1 appears to have 2 poles at LF, one is C2R6 the other is C5-whatever gives the optocoupler (no idea how the freq response and impedance looks like). If these two poles happen to be close in frequency, when you close the loop the LF response may overshoot. You need a zero to compensate the second pole, a resistor in series with C2 will do.
P.S. The closer the poles are, the higher the overshoot. 1.5dB as reported is not that bad, you can leave it as it is and happily live ever after.
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