Duty cycle control circuit and applications to frequency dividers

A duty cycle control circuit for clock signals is presented. The proposed circuit uses a rising edge detector to generate one shot output signals which have the same frequency of the input clock signal. A pulse width controllable monostable multivibrator converts the one shot signals into rectangular pulses. By using the feedback control voltage from an operational amplifier, the pulse width of generated rectangular pulses is automatically adjusted to a pre-set duty cycle. As compared to prior arts, features of this proposed circuit include simple design, low cost and less power. Furthermore, a novel design approach for frequency dividers by the proposed duty cycle control circuit is also demonstrated