Semtech Corporation

Steven M Granger

Kun Xing

Min Mao

Described herein are systems and methods for providing a variable switching frequency for a power supply. The system includes a controller and a filter. The controller generates a switching frequency for a power supply. The switching frequency is modified as a function of an input voltage and an output voltage. The filter provides the output voltage to a load based at least in part on the switching frequency generated by the controller. In one example, the controller adaptively modifies the switching frequency as a function of the input voltage and the output voltage in order to maintain a peak to peak current for an inductor.

Adaptive switching frequency adjustment for a power supply

According to one aspect of the teachings herein, a DC-to-DC converter operates according to an advantageous constant on-time topology that reduces output voltage ripple during light load conditions. The converter produces an output voltage by driving high-side and low-side switches in an inductor-based switching circuit, and regulates the output voltage by varying the on-time of a low-side switch, while holding the on-time of the high-side switch constant. Advantageously, the converter shortens the on-time of the high-side switch during light load conditions, which reduces the output voltage ripple. Thus, the converter may be understood as using a first, constant on-time for the high-side switch during 'normal' operations and a second, shorter on-time for the high-side switch during light load conditions.

Growing community of inventors

Apex, NC, United States of America

Steven M Granger