[sdiy] CS80 Filter IC schematic

[The Old Crow]

  I used standard OTAs to make the gain cells in my CS80 filter 
equivalent.  CA3280s, to be exact.  Ideally, you need to match the OTAs in 
sets of 3 for best performance, e.g., the same Iabc for each OTA yields 
the same fraction of gain.  You want as much Iabc vs. input signal as 
possible for minimum noise, thus the use of 3280s.

Crow
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On Mon, 24 Jan 2005, Antti Huovilainen wrote:

> On Mon, 24 Jan 2005, JH. wrote:
> 
> > http://home.debitel.net/user/jhaible/cs80_vcf_spice_jh.pdf
> 
> Thanks for the info. How are the gm cells implemented?
> 
> Antti