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From: shers@mit-caf.MIT.EDU (Alexander The Great                                                                     Sherstinsky)
Newsgroups: comp.lsi
Subject: A Question On Biasing Circuits
Message-ID: <4025@mit-caf.MIT.EDU>
Date: 3 Mar 90 18:45:11 GMT
Reply-To: shers@mit-caf.UUCP (Alexander The Great                                                                     Sherstinsky)
Organization: Microsystems Technology Laboratories, MIT
Lines: 27

Vi   C
----||----*-- Vo
          |
          /
          \ R
          /
          \
          |
          GND
         
I need help in finding the right circuit for my thesis.  Basically,
I am designing a highpass RC filter whose break point frequency is as
small as I can get.  C is fixed at 1pF, so the objective is to make R big.
Thus, what I need is a biasing network that will keep the node Vo 
at 2.5 V DC, while making the R huge.  The supply voltages are 0 V and 5 V,
which is why I want an approximately 2.5 V DC level.  It looks like what
I want is a voltage source with a huge source impedance (1 Gohm would 
be nice).  It doesn't have to be linear, the whole circuit doesn't have
to be linear.

Thanks for help,
Alex
-- 
+-------------------------------+------+-----------------+---------------------+
|Alexander The Great Sherstinsky|me    |shers@caf.mit.edu|To become as refined |
|Alexander Semyon Sherstinsky   |myself|shers@caf.mit.edu|a person as possible.|
|Alex Sherstinsky               |I     |shers@caf.mit.edu|*********************|