Need suggestion for Current Reading via Resistor

[sayzer]

HenrikOlsson,

Thanks for your input.
Schematic is just to show the concept.
As you said, I will use a 0.1 or 0.05 ohm resistor.

Based on my experiences, amateur experiences, PWM with direct gate drive ,is never the same as with a resistor (from Mosfet S to GND).

[Tywais]

I've just joined so apologies to responding to older topics. Will respond to only topics where last responses that are within two weeks to prevent digging up 1-2 year old posts.

You can make a poor man's differential amplifier. Make a pair of voltage divider resistors so at 24V you have 5V at the center. Attach one from A to gnd and the other from B to ground. Feed the two signals into two ADC channels on a PIC, read them and subtract the values from each other. This will give you the voltage across the resistor therefore the current. Not knowing the expected current though the voltage levels may be too small without using a low Vref to the PIC.

I've done this with a high power adjustable current regulator where I have to monitor the voltage across the output load where one end is tied to 24V.