HOW TO – Multiplex analog readings – what can go wrong with (high impedance) sensors and how to fix it!

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A user in the customer forums had a problem with multiplexing analog signals, they seemed to be very noisy and inconsistent. Turns out it was because the sensors are high impedance. This means that if there is capacitance on the ADC line or on any sort of sample&hold capacitor, it may take a while for it to charge up. Read these threads for some great analysis! View here and here



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1 Comment

  1. Thanks for posting this! I’d like to see more links to helpful information like this from time to time.

    Comment by FazJaxton — January 30, 2010 @ 4:34 pm

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