Comparison of single-wire protocol circuit and method based on a duty ratio

The present invention relates to a comparator circuit based on a duty cycle of the single wire protocol, comprising: an input terminal connected to an input PWM signal edge detection circuit, addition and subtraction counter counter, wherein the counter and the clock input of the adder is also connected to the down counter count clock edge detection the signal detecting circuit is inputted to the up-counter and down counter, the counter and the subtraction output of the adder are latched counter output pulse signal is connected into the adder. The method of the present invention, the duty cycle of the comparison circuit and single wire protocol-based, since the voltage is too low or too high for the absence of the comparison of the conventional analog comparator circuit charging mode, it is possible to sufficiently broad range of frequencies and duty cycle variations in under the scope to achieve accurate, relatively fast duty cycle.