DC to DC converter and pwm controller with adaptive compensation circuit

Abstract

DC to DC converters and PWM controllers are presented in which a slope compensation ramp signal is provided for current control operation via a frequency adaptive compensation circuit with a phase locked loop that provides a control output signal having an amplitude generally proportional to the frequency of a clock signal, and a slope generator circuit generating the slope compensation ramp signal with an amplitude generally proportional to the control output signal amplitude.

Description

technical field [0001] The present invention relates to a DC-DC converter and a PWM controller with frequency adaptive slope compensation circuitry. Background technique [0002] A DC-DC converter is a switching power supply that converts received input power to provide a controlled DC output by operating one or more switching devices. Various forms of DC-DC converters have been developed, including buck converters, which regulate the output voltage to a level substantially smaller than the input voltage, and boost converters, which are capable of providing an output voltage higher than the input voltage level. Typically, converter switching devices are operated in a closed-loop manner with pulse width modulation (PWM) for voltage-mode control, where the PWM duty cycle is adjusted based on an output voltage feedback signal. Current mode control techniques are sometimes used where an inner current control loop and an outer voltage control loop are used. One type of current ...

AI Technical Summary

Problems solved by technology

However, the operation of the DC-DC converter thus depends on external components to provide a compensation ramp corresponding to the operating frequency, and incorrect selection of external components can cause a mismatch between the actual operating frequency and the compensation ramp

Also, providing ASIC pins for external compensation adjustment is expensive in terms of board area and component cost

Images