I watched EEVblog’s video about debugging a short circuit with
precise multimeter. He determined the direction of shorted place
by comparing resistances in different places. I wanted to debug
like that too and also measure resistances of wires and
connectors, but all cheap multimeters measure only down to 0.1Ω.
To get 10mΩ I have to buy 400€ multimeter. So I searched and
found an article describing cheap and dirty way to measure low
resistances. You need a known voltage source and known resistors
and then you can form a voltage divider and measure the
resistance. Awesome! But the form factor and all the math behind
it sucks, as a plug and play device it would be perfect. I
though about making it its own box, but was almost impossible to
find cheap probe connectors for panel or PCB. So it will be a
one PCB product. First, the concept. - It should measure
resistances from 1Ω to 0.1mΩ - General purpose – can be plugged
in any multimeter. - Output should be in mV, because most
multimeters have mV display. - No ma