[sdiy] Log/exp conversion

[media at mail1.nai.net]

At 9:40 AM -0500 12/22/02, David Reichert wrote:
>
>Anyway, I ve been working on a VCO design, but still need to work in the
>log conversion bit for the 1V/oct. Seems that everything I ve tried so
>far doesn t work. All of my transistor circuits seem to remain linear,
>even in the 0-700mV range. Does anyone know of a good source of
>information on the design of these converters?

While I'm sure there are much more VCO-specific designs on the web, you
might want to go to National's website and download application notes AN-30
"Log Converters", and AN-311 "Theory and Applications of Logarithmic
Amplifiers".