Systems, methods and apparatus with extended pulse width modulated phase offset

Abstract

Extending the PWM phase offset when generating a phase-shifted PWM signal group is achieved by means of a separate phase counter that is independent of the time-base counter used in conventional PWM generation circuits and is prevented from retriggering until the existing duty cycle has completed. This is accomplished with phase offset counters, phase comparators and circuits triggered via an overall synchronized master time base for multi-phase PWM signal generation.

Description

technical field [0001] This disclosure relates generally to generation of groups of pulse width modulated signals, and more particularly to extending a pulse width modulation phase offset of the group of pulse width modulated signals. Background technique [0002] Power conversion applications are becoming more sophisticated to improve their power conversion efficiency, for example, by using arrays (groups) of pulse width modulated (PWM) signal outputs that are phase shifted relative to each other. Current newer PWM control designs use multiple sets of these PWM signals phase shifted relative to each other to control multiple power transistors with the output combined into a single very low ripple DC power switch mode power supply (SMPS). This requires a phase shift greater than 360 electrical degrees (greater than one PWM period). Current technology PWM generation circuits cannot support this functionality. [0003] Groups of phase-shifted PWM signals are often used in st...

AI Technical Summary

Problems solved by technology

Using software for this purpose is difficult to do properly at the high frequency pulse rates required for these switch mode power supply (SMPS) applications

Also, when trying to respond to asynchronous events, proper control becomes impossible

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