Digital automatic power control system design

We design a digital automatic power control system based on an automatic current control circuit (ACC) because an automatic current control circuit has the advantage that it doesn´t require a photodiode to sense light intensity and correct output current, and we can adjust the current flowing through a light-emitting diode when the voltages of light-emitting diodes vary with temperature. Reducing the dependence of LED light power on temperature is our main goal. The digital automatic power control system in this paper includes an instrumentation amplifier, a microprocessor, a digital-to-analog convertor and a voltage-to-current circuit.