Switch-mode regulator including hysteretic control
AssigneeFairchild Semiconductor Corporation
InventorsJames Garrett, Christopher D. Bridge
Life of this patent
Estimating the term…
Abstract
This document discusses, among other things, a regulator circuit. The regulator circuit can controllably connect a first voltage to an inductor using a first switch and can controllably connect a second voltage to the inductor using a second switch. The first switch can be turned off and the second switch can be turned on for a duration proportional to a difference between the first voltage and a third voltage, divided by the first voltage. The first switch can be turned off and the second switch can be turned on for a duration proportional to the third voltage divided by the first voltage. One of the first or third voltages can correspond to a desired output voltage.
Claims20
A regulator circuit, comprising:
- a first switch configured to controllably connect a first voltage to an inductor;
- a second switch configured to controllably connect a second voltage to the inductor;
- a switch control circuit configured to control the first and second switches using a timer circuit;
- wherein the switch control circuit is configured to turn off the first switch and to turn on the second switch for a duration proportional to a difference between the first voltage and a third voltage, divided by the first voltage;
- wherein the switch control circuit is configured to turn on the first switch and to turn off the second switch for a duration proportional to the third voltage divided by the first voltage;
- wherein one of the first or third voltages corresponds to a desired output voltage;
- wherein the second voltage is less than the first and third voltages;
- and
- wherein the switch control circuit includes at least one of a peak threshold control circuit and a valley threshold control circuit and wherein the switch cycling period is adjustable using the at least one of the peak threshold control circuit and the valley threshold control circuit.
A method, comprising:
- controllably connecting a first voltage to an inductor using a first switch;
- controllably connecting a second voltage to the inductor using a second switch;
- turning off the first switch and turning on the second switch for a duration proportional to a difference between the first voltage and a third voltage, divided by the first voltage;
- and
- turning on the first switch and turning off the second switch for a duration proportional to the third voltage divided by the first voltage, wherein one of the first or third voltages corresponds to a desired output voltage, and wherein the second voltage is less than the first and third voltages;
- and
- adjusting a switch cycling period using at least one of a peak threshold control circuit and a valley threshold control circuit.
Dependencies are inferred from the claim text.