[sdiy] Expo in one chip?

[Neil Johnson]

KD KD wrote:
> I had hoped the external input stability filters to be removed
> by a upgraded design type Doug Curtis.

The SSM2018 had an internal compensation system, but that is applied
per-channel (the SSM2018 was single channel).  Replicating that in the
2164 would either require three extra pins per channel, or a global
compensation system which would preclude certain circuit
configurations.  Sticking with the existing scheme is not a bad
compromise.

> All i can see/read is the usual protection diode between -V and AG,
> datasheet page 3.

Which version of the datasheet do you have?

> 5k to 10k are'nt much, one could have hoped for a "open base summing point"
> upgrade instead.

Again, it's a matter of compromise - for the common case this would
need an external resistor per channel.

Neil
-- 
http://www.njohnson.co.uk