CIRCUIT AND METHOD FOR DETECT DUTY RATIO OF PWM SIGNAL

摘要

The present invention relates to a circuit and a method for detecting duty ratio of a pulse width modulation (PWM) signal. The circuit for detecting duty ratio of a PWM signal of the present invention includes: a counting unit for counting PWM signals; a detection instruction determining unit for determining the input of a detection instruction signal which instructs a detection start regarding a duty ratio of the PWM signal; an edge detecting unit for detecting a PWM edge which is set in advance from the PWM signal; and a duty calculating unit for calculating the duty ratio of the PWM signal by using a count value of the counting unit regarding a section from a k^th time point (T(k), k is a natural number which is equal to or more than 1) at which the PWM edge is detected after determining the input of the detection instruction signal to a (k+1)^th time point (T(k+1)) at which the PWM edge is detected after determining the next input of the detection instruction signal. [Reference numerals] (100) Counting unit; (200) Detection instruction determining unit; (300) Edge detecting unit; (400) Duty calculating unit