Reply-To: "Kevin Aylward"
From: "Kevin Aylward"
References: <3D760B64.CC303206@scs.uiuc.edu> <3D763949.4B6D795E@scs.uiuc.edu> <firstname.lastname@example.org> <email@example.com> <3D808AAC.B0C1DDA3@cern.ch>
Subject: Re: High impedance low noise
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Date: Thu, 12 Sep 2002 14:23:40 +0100
NNTP-Posting-Date: Thu, 12 Sep 2002 14:23:41 BST
"Jeroen Belleman" wrote in message
> Kevin Aylward wrote:
> > "James Meyer" wrote in message
> > news:firstname.lastname@example.org...
> > >[...] You won't find a lower noise device than the U430. It's
> > >fast too.
> and Kevin Aylward wrote:
> > I have not checked it data sheet for this one, but does it beat the
> > 2sk162 (dual) which generates only 0.65 nv/rthz, with a very low 1/f
> > corner.
> The U430 is 6nV/rtHz, but with 5pF input capacitance. I
> haven't seen a data sheet for the 2SK162, but I'd guess
> it to be 10 times that, if not worse. Can you still get
> I'm interested: Can you complete my table of figures?
> U430 2SK152 2SK162 BF862
> Ciss 5pF 8pF ? 10pF
> Vn/rtHz 6nV 1.2nV 0.65nV 0.8nV
> Gm (@10mA) 15mS 25mS ? 35mS
> 1/f corner ? 300Hz ? ?
> As for the U430, I think the BF862 blows it out of the
> water in almost all applications. For the 2SK162, I don't
> know. Maybe a parallel pair of BF862s still wins.
Er.. its been maybe 15 years when I looked at it, so I cant remember of
hand. It might be around 20p, certainly not much higher, maybe lower.
Its 1/f corner was something like 10Hz.
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