I have an analog circuit that has a (normally) negative polarity DC
feedback signal. I'd like to change the gain of the circuit digitally,
so I'd like to use a digital pot. The problem is that a digital pot can
only take signals between VEE and VDD - most usually probably 0v to 5v.

My rails are +5/0/-5 and my feedback lies somewhere between 0 and -5.
Has anyone encountered a digital pot that can either take a 10v supply,
or has level shifters on the digital lines? I think I might be able to
use a CD4052 with discrete resistors, but then it's a 16 pin chip I have
to put on the board.

Any ideas?

-
Martin
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