Patent attributes
A digital pulse-width modulator is provided that receives a digital command input signal and a secondary control input signal and provides a pulse-width-modulated output signal. The pulse-width-modulated output signal comprises a pulse-width that corresponds to an integer number of slots each having a time duration. The integer number of slots corresponds to a value of the digital command signal, and the time duration is determined based upon the secondary control input signal. In one embodiment, the digital pulse-width-modulator comprises a plurality of delay cells arranged in series for propagating a clock signal through the plurality of delay cells. A time delay for each of the delay cells is determined by the secondary control input signal. A controller is enabled to set the output signal to a first value at the start of a propagation of the clock through the plurality of delay cells and to set the output signal to a second value when the clock signal propagates to one of the delay cells identified by the digital command signal. In another embodiment, the digital pulse-width-modulator is used with a switched-mode power converter. A digital command signal based on a feedback signal from the converter and a secondary control signal derived from an input voltage of the converter are received by the digital pulse-width-modulator. The digital pulse-width-modulator provides a pulse-width-modulated output signal based on the digital command signal and the secondary control signal. The output signal is then provided to the converter to control at least one switch of the converter.
