Serial pwm signal decoding circuit and method based on a capacitor charge-discharge structure and method thereof

Abstract

The present disclosure provides a serial PWM signal decoding circuit based on a capacitor charge-discharge structure, comprising: a timing logic generation circuit configured to receive, at an input end of the timing logic generation circuit, a PWM differential signal, and generate a timing logic signal; and at least two capacitor charge-discharge decoding modules, each of the at least two capacitor charge-discharge decoding modules has an input end connected to an output end of the timing logic generation circuit, and is configured to perform charging and discharging based on the timing logic signal. During a decoding process, a voltage at a charge-discharge capacitor of the capacitor charge-discharge decoding module before the charging and discharging is a common mode voltage VCM, and a voltage at a charge-discharge node after the end of the charging and discharging is a voltage V, and the PWM signal is decoded by identify the PWM signal through determining a polarity of a voltage difference between the common mode voltage VCM and the voltage V. The present disclosure further provides a method of decoding based on a capacitor charge-discharge structure. The present disclosure provides a simple structure and does not need synchronize code streams, thus avoiding the use of a complicated CDR and an oversampling structure, realizing the decoding of PWM signals at different rates, increasing the efficiency of signal transmission and lowering the power consumption.