Patent ID: 7816900

Claim:
A correction circuit for use in correcting a duty cycle for pulse width modulation of a switched power supply to match an inductor current of the power supply to a load current, the correction circuit comprising: a first comparator operable to compare the inductor current to the load current and to provide a current difference signal; a first multiplier operable to multiply the current difference signal by an inductance value of the inductor of the switched power supply; a second comparator operable to compare an input voltage of the switched power supply to an output voltage and to provide a voltage difference signal; a divider operable to divide the output of the first multiplier by the voltage difference signal; and a second multiplier operable to multiply the output of the divider by the frequency of the switched power supply to provide a correction value for use in adjusting a duty cycle of the pulse width modulation of the power supply such that the inductor current matches the output current.