Digital pulse width modulation controller

摘要

A digital pulse width modulation controller includes a pulse width modulation controller, a selection unit having at least one selector, a comparison unit having at least one comparator, and a signal conversion unit having at least one digital-to-analog converter. The digital-to-analog converter generates a reference current and/or voltage. The comparator receives the reference current and/or voltage, and performs a comparison operation to generate a comparison signal based on a feedback signal. The selector selects one selection signal to input into the pulse width modulation controller, which receives other parameters set by a user or the system at the same time so as to control characteristics of the digital pulse width modulation signals, thereby improving the electric properties of a loading circuit.

主权项

1. A digital pulse width modulation controller for generating at least two digital pulse width modulation (PWM) signals used to drive a loading circuit, comprising:
a signal conversion unit including at least one digital-to-analog converter (DAC), each receiving a different reference signal and generating a corresponding reference voltage and/or current; a comparison unit including at least one comparator for receiving the reference voltage and/or current from the corresponding DAC of the signal conversion unit, performing a comparison operation, and generating a comparison signal with a low or high level based on a feedback signal from the loading circuit; a selection unit for receiving a selection signal and the comparison signals from the comparison unit and including at least one selector for selecting one selection signal serving as an input signal based on the selection signal; and a pulse width modulation (PWM) controller for receiving the input signals from the selection unit and/or parameters preset by a user or a system, and controlling a number of resolutions of a duty of the digital PWM signals based on at least one determination rule to change a dead time interval between the digital PWM signals, wherein the resolution is a minimum changeable unit of the duty, and the dead time interval is a time interval when the digital PWM signals are low level.