Switched power stage with inductor bypass and a method for controlling same
The disclosure relates to a method of generating an output voltage from a high input voltage and a command signal, the method comprising: providing an inductor having a first terminal and a second terminal linked to a low voltage by a capacitor, the second inductor terminal supplying the output voltage to a load, the low voltage being lower than the high input voltage; and connecting the first inductor terminal either to the high input voltage or to the inductor second terminal, as a function of the command signal.
1. A switched power stage comprising:
an inductor having a first terminal linked to a high voltage source by a first switch;
a capacitor linking to a low voltage source a second terminal of the inductor, the second terminal of the inductor forming an output of the switched power stage;
a second switch linking the first terminal of the inductor to the low voltage source;
a third switch connected between the first and second terminals of the inductor; and
a controller configured to operate the first switch, second switch, and third switch so as to regulate the output of the power stage by closing the first switch, with the second switch and third switch open, for a first portion of a switching period, closing the third switch, with the first switch and the second switch open, for a second portion of the switching period following the first portion of the switching period, closing the second switch, with the first switch and third switch open, for a third portion of the switching period following the second portion of the switching period, and closing the third switch, with the first switch and the second switch open, for a fourth portion of the switching period following the third portion of the switching period.
2. The switched power stage of claim 1 , wherein the first portion of the switching period and the third portion of the switching period are of the same duration.
3. The switched power stage of claim 1 , wherein the second portion of the switching period and the fourth portion of the switching period are of the same duration.
4. The switched power stage of claim 1 , wherein the first portion of the switching period and the third portion of the switching period are of the same duration and wherein the second portion of the switching period and the fourth portion of the switching period are of the same duration.