Junction Noise

[Osamu Hoshuyama]

Hello Tim,

> Date:    Thu, 07 Sep 2000 12:01:23 MST
> From:    Tim Ressel <Tim_R1 at verifone.com>
> 
> I've had a request to do some heavy-duty analysis on the pinkfet circuit.
> However I cannot find a 2SK241, except for one place that wants a $25 minimum
> order. Does anyone have one these they could part with? I'm sure some deal coul
> d
> be arranged.

2SK241 is one of the cheapest MOS FETs in Japan.
I myself have never tried the circuit. But, I guess in the first test,
any depletion type MOS FET will be OK.  (Do NOT use enhancement type.)

Mr. Kasahara who presented the circuit says in the page (Sorry for my
poor translation):
  I'm interested in noises.  I obtained good results from a circuit.
  So, I report it.  I used a MOS FET, which is (generally) said
  to generate more 1/f noise than bipoler Tr.  I measured the output
  signal using the FFT analizer of my school/univ.  The noise voltage
  divided by the gain of opamp (100) is shown in the figure bellow.
  ......(snip) 

Hope this helps.
- -- ---- ----------- --- --- - ----- -- --- --- - - ------ - - - --
 Osamu HOSHUYAMA          Digital Signal Processing Technology Group
                    C&C Media Research Laboratories, NEC Corporation
               Email: houshu at ccm.CL.nec.co.jp,  Fax: +81-44-856-2232
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