Method to recover from current loop instability after cycle by cycle current limit intervention in peak current mode control

摘要

A method of controlling a switching voltage regulator includes detecting current-limit events indicating a maximum inductor current threshold has been exceeded. A compensation voltage that determines a duty cycle and thereby an inductor current is controlled to reduce the inductor current and eliminate the occurrence of current-limit events. The method detects whether a time for which no current-limit events have been detected exceeds a time step threshold. The compensation voltage is controlled to increase the duty cycle and thereby the inductor current in response to the time exceeding the time step threshold. The time step threshold may be an integer number of switching cycles of the voltage regulator.