Kind of 8052 off-topic, but wanted to use such a circuit with my 8052 based controller. I will be using the onboard PWM to produce a 0-5v 8-bit output.

I'd like to design a circuit that converts the voltage proportionally to current without affecting the voltage. So for example, at 0 volts out, 0mA at 5v (theoretically) is generated. At 2.5 volts, 50mA at 5v is generated. At 5v, 100mA at 5v is generated.

Anybody ever done anything like this? Any reading or subjectstechniques you could recommend I look into?

Thanks a LOT in advance,
Phil