STM32 Open Source Multimeter

Then there are features – those cheap multimeters almost never have digital data output for automated measurements, they don’t measure RMS, they cannot measure power (ie voltage and current at the same time), you need to turn a large dial to switch ranges and so on. As I said, I am not aiming at fully replacing a commercially made multimeter – my goal is mostly having something small, cheap and accurate, capable of measuring voltage and current, because those things usually change in your circuit-under-test and you need to measure multiple of these at the same time. The meter features 6 “modes”, shown on the picture below:

Voltage can be measured in two ranges: ±60 V and ±6 V. I choose these ranges because very often I work with circuits powered by 5 V, so the 6 V range is very handy.

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