Abstract: A method and system for controlling a DC-DC converter compares the output voltage with a low threshold and a high threshold, and injects a certain minimum electric charge into an inductor of the converter during a charge period corresponding to a power switch. The beginning of a charge period is commanded each time the output voltage drops below the low threshold, and the electric charge transferred during a charge period is progressively increased until the output voltage rises to the high threshold. The output voltage starts from the low threshold upon executing the charge period. The duration of the time interval between two consecutive charge periods is measured and stored. The current time interval is compared with the previously detected and stored time interval. The output voltage is decreasing to the minimum electric charge whenever an increment of the time interval between two consecutive charge periods is detected.