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<DIV><FONT face="Comic Sans MS">While thumbing thru some notes, I found
references to a couple of articles that might be of interest (or at least make
for good reading for aspiring analog gurus!). </FONT></DIV>
<DIV><FONT face="Comic Sans MS">1. EDN Magazine, May 16, 1985 pp153-164 "Design
techniques extend V/F converter performance" (part 1 of 2)</FONT></DIV>
<DIV><FONT face="Comic Sans MS">2. EDN Magazine, May 30, 1985 pp239-248 "Refine
V/F converter operation with novel design techniques" (part 2 of 2)</FONT></DIV>
<DIV><FONT face="Comic Sans MS">These were written by Jim Williams of Linear
Technologies, who I think also did the vco circuit in National's "famous" AN299
when he was with them. Not much on exponential converters per se, but more on
making wide range VCOs.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face="Comic Sans MS">Also, I just ran across what I guess to be
an update of these articles: <A
href="http://www.linear.com/cgi-bin/database?function=elementinhtml&filename=AppNote.html&name=AppNotes&num=20">AN14
"Designs for high performance voltage to frequency converters"</A> also by Jim
Williams. I'd guess this is available from LT's web site. One circuit (p15) is
an exponential VCO using the CA3096AE for log and thermal control functions. It
claims a drift of 150ppm/degree C and exponential conformity of 0.13% over 10Hz
to 20KHz.</FONT></DIV>
<DIV><FONT face="Comic Sans MS"></FONT> </DIV>
<DIV><FONT face="Comic Sans MS">And, there's a version of the AN299 circuit on
the data sheet for the <A
href="http://www.linear.com/cgi-bin/database?function=elementinhtml&filename=DataSheet.html&name=DataSheet&num=117">LT1055/LT1056
BiFET opamp</A>, using the CA3096AE also.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face="Comic Sans MS">I'm curious, who has better specs: CA3045,
CA3046, or CA3096AE?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face="Comic Sans MS">FYI,</FONT></DIV>
<DIV><FONT face="Comic Sans MS">Michael</FONT></DIV>
<DIV><FONT face="Comic Sans MS"><A
href="mailto:mlloyd1@enteract.com">mlloyd1@enteract.com</A></FONT> </DIV></BODY></HTML>