[sdiy] FSR-controlled CV/LED

[David G Dixon]

Hey Derek,

I would first try to measure the force-resistance response of the FSR (but,
really, it should be given in the datasheet).  Then, if it is an exponential
response (as it seems to be given your description), then you should use a
logarithmic converter to convert it to a linear voltage.

Without knowing more or doing my own research, and just thinking aloud, I
would just say that this sounds like an excellent application for a 2164
VCA.  Putting one of those in the feedback loop of an opamp makes an
excellent (nearly ideal, in fact) logarithmic converter, and, of course, the
CV response of an unaided 2164 VCA is exponential.  Somewhere inbetween
those two responses, you should be able to get what you want from your FSR.