On 11/22/06, Gerhard Fiedler <lists@connectionbrazil.com> wrote:
>
>
> Using it with 16 thermocouple inputs, it seems you're working against the
> design of this device (unless you use 16 of them). Use a traditional ESD
> protection and break detection on each input, add possibly a differential
> amplifier for each input (alternatively only one after the mux), mux that
> into an ADC, add a simple cold junction temperature sensor and do the
> compensation and linearisation in firmware. This sounds like a lot of
> stuff, but it's probably easier than trying to multiplex such an active
> input that wasn't designed to be multiplexed.
>
> Gerhard


I am leaning on going down this path of doing all of the linearization and
cold-junction compensation myself, depending on how my testing goes with the
current circuit.  As soon as I can get my hands on a thermocouple calibrator
so I can see if the circuit I designed has decent accuracy with the Max6675,
I may stick with it.  However I am not fond of Maxim's small order policies
nor am I fond of being dependent on a propriatary chip.  So we'll see.

Thanks again for the help gents.

Regards,
Bob
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