US 2017/0257031 A1 · INDUCTOR CURRENT BASED MODE CONTROL FOR BUCK-BOOST CONVERTERS

Abstract

Apparatus and methods for controlling voltage converter are provided, in an example, a switched-mode DC-DC voltage converter can include an inductor, at least four switches coupled to the inductor and configured to direct current through the inductor to provide a desired output voltage at an output voltage terminal of the voltage converter using an input voltage supply and a ground reference of the converter, and a controller circuit, configured to receive an indication of inductor current through the inductor and to use the slope of the inductor current to control a change between two operating modes of a group of operating modes that include a boost operating mode, a buck operating mode, and a buck-boost operating mode.

Claims21

Dependent claims

A method of operating a switched-mode DC-DC voltage converter, the method comprising:

during a first machine state, isolating an output voltage terminal of the converter from an inductor of the DC-DC voltage converter and from a ground potential;
during a second machine state, establishing inductor current in an inductor of the converter using an input voltage supply, a first transistor and a third transistor;
during a third machine state or during a fifth machine state, coupling the input voltage supply to the output voltage terminal via the inductor using the first transistor and a fourth transistor;
during a fourth machine state, coupling the output voltage terminal to the ground potential via the inductor using a second transistor and the fourth transistor;
and
transitioning from the fifth machine state to the fourth machine state when a slope of the inductor current over a first slope check delay period is less than a first slope threshold.

3 more elements

A control circuit of a voltage converter, the control circuit comprising:

a controller circuit configured to control current through an inductor of the voltage converter using four switches coupled to the inductor;
a current slope check delay generator configured to generate a current slope check delay,
wherein the controller circuit is configured to initiate the current slope check delay when the inductor is coupled to an input voltage via a first switch of the four switches and to an output voltage via a fourth switch of the four switches, to compare a level of current through the inductor at the conclusion of the current slope check delay with a reference current level, to set a current slope variable based on the comparison of the level with the reference current level, and to change a machine state of the controller based on a first state of the current slope variable.

A switched-mode DC-DC voltage converter, comprising:

an inductor;
at least four switches coupled to the inductor and configured to direct current through the inductor to provide a desired output voltage at an output voltage terminal of the voltage converter using an input voltage supply and a ground reference of the converter;
and
a controller circuit, configured to receive an indication of inductor current through the inductor and to use the slope of the inductor current to control a change between two operating modes of a group of operating modes that include a boost operating mode, a buck operating mode, and a buck-boost operating mode.

1 more element

Dependencies are inferred from the claim text.

Inductor current based mode control for buck-boost converters

Life of this patent

Inductor current based mode control for buck-boost converters

Life of this patent

Abstract

Claims21