Isolated Voltage measurement

hello everyone,
i'm designing a DC Chopper ( more like boost converter but with higher gain) that takes input 12-24v dc and steps it up to 200v dc
i need to measure 4 values

  • input current ( current waveform looks like continious ramp up and down)
  • input voltage (varies between 12v and 24v )
  • OUTPUT current (dc current less than 0.5A
  • OUTPUT voltage (DC voltage up to 200V )

i connected the ground of the arduino the o/p -ve terminal so now i can measure output voltage and current using voltage dividers and series resistor
the problem is now i need to measure the input values ( V& i) but i can't connect arduino ground to -ve terminal of the input source(Battery)
(i.e. no common ground )
any suggestions ?
noting that i tried

  • Voltage to frequency but failed
  • isolated Serial communication and also failed :o

Show the complete circuit diagram including the bits that didn't work.

Analog opto-couplers are designed for precisely this role.

Explain more though, I'm surprized the Arduino is on the output side, its more
normal to do all the control on the low voltage side.