Tracker ONE - Analog sensor reading and publishing

What peekay123 said. I like to use 10K on the high side and 18K on the low side, which leaves a little safety margin and uses standard resistor values. It has a maximum of 3.214V.

The other thing I like to add is a D1213A dataline protection diode and TVS. It protects both against transients and also if the input exceeds 3.3V. The D1213 saved me once when I was using a 12V powered sensor with a 0-5V output with a similar voltage divider. I discovered if the sensor ground was loose it would output close to 12V on the 5V output, which would have fried the ADC if not for the protection diode.

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