Patent ID: 8203281

Claim:
A LED driver circuit for powering a plurality of light emitting diodes with a power source, said circuit comprising: a DC-DC converter powered by said power source, said DC-DC converter for providing current to said light emitting diodes, said DC-DC converter controlled by a microcontroller through pulse width modulation (PWM); a current feedback circuit for measuring the output of said DC-DC converter, said current feedback circuit comprising a measurement resistor connected in series with said light emitting diodes, wherein voltage measured across said measurement resistor is filtered by a filter and amplified by an operational amplifier to create an analog amplified signal; and said microcontroller, said microcontroller for generating a digital reference current, said microcontroller comprising an analog to digital converter for converting said analog amplified signal to a digital measured current, said microcontroller comprising a PWM generator for generating a PWM signal based on the difference between said measured current and said reference current, said PWM signal for controlling current output of said DC-DC converter.