> Short comment to start the ball rolling.
> If 10 milliohms is acceptable, as you seem to suggest, then you get 10 mV=
/A
> or 50 mV at 15A.
> That's usefully more than the input offset voltage of many low cost
> comparators.
> Unadjusted many are in the +/- 5 to 10 mV range. So about 0.5 to 1 A
> uncertainty at max Voffset.
> Not "precise". but you do not need precision,
>=20
> Many more modern low cost comparators have Vddma in the 5-10V range.
> Bearable with design.
> The very cheapest are often variants of the olde olde LM339 with 30V+
> supply voltage ratings.

This is why I suggested using a high side current sense chip like the Linea=
r Technology LTC6101, LTC6102, LT6106 or Microchip PAC1921. These would wor=
k with a PCB trace at about that resistance and feeding that into an ADC wo=
uld allow configurable current monitoring.



--=20
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