Abstract: Techniques for measuring average inductor charging current in a switched-power circuit avoid incurring measurement delay or a requirement of a complex filter. An inductor charging current measurement circuit coupled to a power output stage of the switched-power circuit measures an average charging current in an inductor of the switched-power circuit using pair of capacitors to sample an output voltage of the power output stage at different cycle times of an inductor current waveform. The measurement circuit includes a switch that connects the pair of capacitors together to provide a measurement indicative of the average inductor charging current by sharing charge between the first capacitor and the second capacitor to provide the measurement voltage. The provided measurement voltage is indicative of an average of an estimated peak and an estimated valley of the inductor current waveform, which may be used to make determinations regarding a magnitude of the load current.

Abstract: A switched- capacitor summer 400 includes an operational amplifier 206 having an input and an output, first and second parallel capacitors 307, 401, first switching circuitry 308, 404 and second switching circuitry 402, 403. First switching circuitry 308, 404 discharges first capacitor 307 during a first timing phase and couples second capacitor 401 between the input and the output of operational amplifier 306 during a first timing phase. Second switching circuitry 402, 403 couples a first capacitor 307 between the input and output of operational amplifier 306 during the second phase to transfer charge from capacitor CS to capacitor 307 and charge up capacitor CH during the second phase.