Patent ID: 8525495

Claim:
An input current generator for a buck-boost circuit, comprising: a current sensor outputting an inductor current signal representing an inductor current of the buck-boost circuit; an input current synthesizer receiving the inductor current signal and outputting a selected signal representing the inductor current signal or a zero signal based on an operating mode of the buck-boost circuit; a current averaging circuit integrating the selected signal and outputting an integrated current signal representing an average of an input current to the buck-boost circuit; and a buck-boost controller receiving the integrated current signal for outputting a pulse-width-modulated signal for controlling the buck-boost circuit, said buck-boost controller including: a PWM controller providing a master pulse-width-modulated signal; a clock providing a clock signal; and a PWM splitter to receive the master pulse-width-modulated signal and the clock signal to provide a first pulse-width-modulated signal to control a first switch and a second pulse-width-modulated signal to control a second switch, the PWM splitter including: a PWM-to-digital converter to provide a first digital signal and a second digital signal, the first digital signal represents a period of the master pulse-width-modulated signal and the second digital signal represents an amount of time at which the master pulse-width-modulated signal is at a value of zero; a control module to receive the first and second digital signals to provide a digital buck control signal and a digital boost control signal, a first digital-to-PWM module to receive the digital buck control signal, the first and second digital signals to provide the first pulse-width-modulated signal; and a second digital-to-PWM module to receive the digital boost control signal, the first and second digital signals to provide the second pulse-width-modulated signal.