Abstract: A method of controlling the charging of a bootstrap capacitance incorporated into a switching regulator of a power transistor includes the steps of comparing, at each switching cycle, the voltage value at the bootstrap capacitance and a predetermined threshold voltage, to change the mode of operation of the regulator following said comparison. More particularly, the control on the transistor is taken off the regulator when the voltage at the bootstrap capacitance is lower than the threshold voltage, while the transistor is forced into the "on" state through a full cycle. In this way, the minimum current to operate the regulator can be minimised.

Abstract: Switching losses in a DC-to-DC converter idling in a pulse-skipping mode are reduced by inhibiting any intervening turn-off command by a PWM control loop of the converter for as long as the current through the inductor of the converter remains below a minimum threshold value set by a dedicated comparator. The method is implemented by employing a comparator with a certain hysteresis and by logically masking the switching to a logic "0" of a high frequency clock (switching) signal of the converter for the entire period of time the current in the inductor remains below the minimum threshold.