Apparatus and method for generating multi-phase pulse width modulation (PWM) and sharing a common (master) duty cycle value among a plurality of PWM generators

摘要

A pulse width modulation (PWM) generator featuring very high speed and high resolution capability and the ability to generate standard complementary PWM, push-pull PWM, variable offset PWM, multiphase PWM, current limit PWM, current reset PWM, and independent time base PWM while further providing automatic triggering for an analog-to-digital conversion (ADC) module that is precisely timed relative to the PWM signals. Applications include control of a switching power supply that requires very high speed operation to obtain high resolution at high switching frequencies, and the ability to vary the phase relationships among the PWM output signals driving the power supply power components. A single PWM duty cycle register may be used for updating any and/or all PWM generators at once to reduce the workload of a digital processor as compared to updating multiple duty cycle registers.