RGB + W PWM Dimmer Automotive

OK, so I know that I've taken some beating and criticism. Mostly because I haven't done anything like this before so first things first.

Thank you for your input and knowledge. I wouldn't be this far without it.

I would love additional feedback, problems, thoughts on what I have going on here.

  • Vin is from an automotive battery / charging system (9.6 - 15.8V)

  • Arduino power supply should be outputting 8V (trying to keep current at a minimum to prevent 7808 from heating up too much).

  • RHEO1 goes to the OEM dimmer on the car. It's Range is 0-10ohms

  • I've figured 5mA of current going to the OEM dimmer giving me a Voltage Range of 0-50mV.

  • OP amp 741 is to be used to Amplifiy the Voltage Range ~50x to 0-2.56V to be compared against the Internal Reference.

  • The white LED driver (Q1) is meant to send +12 PWM to White LED's which would be grounded where they are.