Power measurement circuit

摘要

A system for power measurement in an electronic device includes a sensing unit, an analog-to-digital converter (ADC) and a controller. The sensing unit senses voltage across a power source and modulates a carrier signal based on the sensed voltage. The ADC converts a combination of the modulated carrier signal and audio signals received by the electronic device to generate a digitized combined signal and provides the digitized combined signal to the controller. The controller separates digitized modulated carrier signal and digitized audio signals. The digitized modulated carrier signal is demodulated to generate an output signal that provides a measure of the power consumed by the electronic device.