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1

The resistors are external, so you have to solder them on PCB and they are not part of IA. The resistors in the table are standard resistors, it shouldn't be a problem to get it from same distributor that will sell you the AI. Example distributor 481 hits for 95.3kohm


1

I would have agreed with the below Cap material choices, NP0/C0G or Film without thinking about it. But after consideration for EMG, you don't need more than 10nF * 10M but for ECG or EEG, you may want 1M*1uF=T. (EMG for muscle signals, ECG for cardio-heart and EEG for brainwaves.) Choosing 0.1uF or more might lead you to expensive or non-existent solutions ...


1

NP0 ceramic capacitors are okay, however larger values tend to be a bit large and expensive. Film capacitors are good, but SMT versions are not so great. Tantalums are not a noise problem but are leaky (and polarized), which might be an issue in your application. X7R and similar class 2 capacitors should probably be avoided- they can exhibit mV level noise. ...


1

The problem was that the 1kΩ RTD-in-series setup was driving the common-mode input on several of the inamps out of their common mode input range, which resulted in noise on their outputs. That noise was then passed on to the ADC, where crosstalk coupled it into all ADC outputs. My previous assessment that "ADC inputs were stable" was incomplete, in ...


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We can't see your layout, so it's impossible to comment on how much, if any, it may be contributing. I would suggest at least the following filter on each RTD input: simulate this circuit – Schematic created using CircuitLab All capacitors are NP0 ceramic types.


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