Switched mode power supply control
AssigneeDelphi Technologies, Inc.
InventorsOsman Musa, Mark W. Gose, Jerry W. Campbell
Life of this patent
Estimating the term…
Abstract
An illustrative example embodiment of a method is for controlling a switch. The switch is used to charge a capacitor that provides an output voltage. The switch has an inductor on an input side between a power source and the switch. The method includes: initiating a switching cycle including turning on the switch, sensing a voltage representing current through the inductor, using a reference voltage as a basis for turning off the switch during the switching cycle when the sensed voltage exceeds the reference voltage, and setting an initial value of the reference voltage at a beginning of the switching cycle based on at least one feature of an activation of the switch during at least one previous switching cycle.
Claims19
A method of controlling a switch that is used to charge a capacitor that provides an output voltage (Vo), the switch having an inductor on an input side of the switch between a power source (Vi) and the switch, the method comprising:
- initiating a switching cycle (k) including turning on the switch;
- sensing a voltage (Vsns) representing current through the inductor;
- using a reference voltage (Vref) as a basis for turning off the switch during the switching cycle (k) when Vsns exceeds Vref;
- and
- setting an initial value of Vref at a beginning of the switching cycle based on at least one feature of an activation of the switch during at least one previous switching cycle (k−n) and reducing Vref during the switching cycle.
A switch control device, comprising:
- a switch that is used to charge a capacitor that provides an output voltage (Vo);
- an inductor on an input side of the switch between a power source and the switch;
- a switching cycle control element that initiates activation of the switch at the beginning of a switching cycle (k);
- a comparator that provides an indication of a relationship between a voltage (Vsns) representing current through the inductor and a reference voltage (Vref), the switching cycle control element turning off the switch during the switching cycle (k) based on the indication from the comparator when Vsns exceeds Vref;
- at least one feedback loop that provides an indication of at least one feature of an activation of the switch during at least one previous switching cycle (k−n), wherein Vref is set to an initial value at a beginning of the switching cycle (k) based on the indication of the at least one feature during the previous switching cycle and Vref is reduced during the switching cycle.
Dependencies are inferred from the claim text.