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<DIV dir=ltr align=left><SPAN class=118420321-26122017><FONT color=#0000ff
size=2 face=Arial>Yes, it's called the V2164, and it is available from Coolaudio
in bulk, or from many retailers (Small Bear, Mammoth, etc). It is a quad
exponential VCA chip. One VCA is used to temperature compensate the
expo, and another is used as the actual exponential converter. It requires
an external summing opamp. A third VCA can be used as a precision
high-frequency compensation current source, leaving the fourth VCA for another
use. This is how all Intellijel VCOs (which I designed) are controlled,
and they have a reputation in euro-land for very decent tracking and
stability.</FONT></SPAN></DIV><BR>
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<FONT size=2 face=Tahoma><B>From:</B> Synth-diy
[mailto:synth-diy-bounces@synth-diy.org] <B>On Behalf Of </B>Jacob
Watters<BR><B>Sent:</B> Tuesday, December 26, 2017 12:49 PM<BR><B>To:</B>
SDIY<BR><B>Subject:</B> [sdiy] Expo in one chip?<BR></FONT><BR></DIV>
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<DIV dir=auto>Expo conversion is require in almost all VCO, VCF and VCA
circuits. Matching transistors and getting the right tempco resistor to be
touching them so they are the same temp is a pain.
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<DIV dir=auto>Has anyone ever made an expo conversion chip that had everything
required in one package? Is it still available?</DIV></DIV></DIV></DIV>
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