O2 sensor buffering/interfacing

[Tom Cloud]

>I am looking for a circuit example to buffer an O2 sensor.  I am unable to obtain the LM9904, and 
>would like an equivalent circuit.
>
>
>
>John C. Lagerquist (vision_a at srv.net)
>Staff Engineer
>Control Vision, Inc.
>
>#include <disclaimer.hpp>
>

John, what is an LM9904 ??

I've come up with a circuit I can share -- and it should
answer another question that's been circulating also -- about
how to force a richer mixture.  The circuit I've seen that was
posted a few weeks back only reduces the amplitude of the signal.
If you were to change the offset reference (is now ground), you'd
be able to keep the amplitude of the EGO swing around "stoich"
while adjusting for richer or leaner.

If anyone is interested, I have the circuit in a GIF format

Tom Cloud

        He laughs last thinks slowest