Patent ID: 8120346

Claim:
A power supply for supplying a current to a load through an inductor, comprising: a control system comprising a PWM controller and adapted to control the current according to an inductor current signal; and a current sensor connected to the inductor and the control system and adapted to generate the inductor current signal according to a sensed current in the inductor, wherein the current sensor comprises: a series combination of a capacitor and a first resistor, wherein the series combination is adapted to be connected in parallel with the inductor with respect to the load; and a second resistor comprising a first terminal connected to a first terminal of the capacitor and a second terminal connected to a second terminal of the capacitor; wherein: the DC impedance of the first resistor, the second resistor, and the capacitor substantially match the DC impedance of the inductor with respect to the control system; and the resistance of the first resistor and the resistance of the second resistor are selected according to a desired voltage range of the inductor current signal.