Logarithmic resistor ladder

[okelk]

Has anybody used a logarithmic resistor ladder instead of the standard r2r ladder before?

correct me if I'm wrong, but wouldn't a d/a converter with a logarithmic response make sense, especially for controlling simple VCOs (4046 and such..) that have a linear response (do they?).

Assuming the vco has a linear response it should be easy to get various equal tempered scales that way...

[elmegil]

You can get better range with less voltage range needed if your VCO core has a log response rather than a linear one. If your hypothetical D/A converter has a logarithmic voltage output, that actually limits the input range unless you have an enormous power supply.

That said, I can see applications where such a thing would be useful, but it's not as much general use.

What would be interesting would be a digital -> current converter that had a logarithmic response, that could drive a core directly without the same kind of limitation to fit inside the rails....

[okelk]