US 11,888,397 B2 · Driver circuit for switching converters

Abstract

A DC-DC switching converter includes power switches selectively coupling an output terminal with a first voltage or with a second voltage. A driver stage is coupled with the power switches for driving the power switches. A driver control stage is coupled with the driver stage for controlling the operation of the driver stage. An output current sensing circuit is coupled with the output terminal and with the driver control stage, and is configured to sense a sign of an output current delivered by the DC-DC switching converter at the output terminal and to generate control signals for the driver control stage. The driver control stage controls the operation of the driver stage according to states of the control signals received from the output current sensing circuit, for selectively delaying the activation of the power switches depending on the sensed sign of the output current.

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Claims14

Dependent claims

A DC-DC switching converter, comprising:

power switches operable to selectively couple an output terminal of the DC-DC switching converter to a first voltage or a second voltage, the output terminal being coupleable to a load when the DC-DC switching converter is in use;
wherein the power switches comprise a first power switch operable for selectively coupling an output terminal of the DC-DC switching converter to the first voltage, and a second power switch operable for selectively coupling the output terminal of the DC-DC switching converter to the second voltage;
a driver stage coupled to the power switches and configured to drive the power switches;
wherein the driver stage comprises:
a first driver stage coupled to and configured to control the first power switch;
and a second driver stage coupled to and configured to control the first power switch;
wherein the first driver stage comprises a first switch, a second switch, and a third switch in series between the first voltage and a first internal reference voltage of the DC-DC switching converter configured to cause activation of the first power switch when applied thereto, wherein the first switch is controlled by a first drive command generated by a control logic of the DC-DC switching converter, the second switch is controlled by a first activation command for the activation of the first driver stage and by a first signal indicative of a voltage level at the output terminal of the DC-DC switching converter, and the third switch is controlled by a first switch control signal depending on the first drive command and on a signal indicative of an activation state of the second power switch;
wherein the second driver stage comprises a fourth switch, a fifth switch and a sixth switch in series between the second voltage and a second internal reference voltage of the DC-DC switching converter configured to cause the activation of the second power switch when applied thereto, wherein the fourth switch is controlled by a second drive command generated by a control logic of the DC-DC switching converter, the fifth switch is controlled by a second activation command for the activation of the second driver stage and by a second signal indicative of the voltage level at the output terminal of the DC-DC switching converter, and the sixth switch is controlled by a second switch control signal depending on the second drive command and on a signal indicative of an activation state of the first power switch;
a driver control stage coupled to the driver stage and configured to control the operation of the driver stage;
wherein the driver control stage comprises:
first driver control stage coupled to and configured to control the operation of the first driver stage, wherein the first driver control stage is further configured to delay the first activation command for activation of the first driver stage when a first control signal is asserted, to receive the signal indicative of an activation state of the second power switch, and to enable the activation of the first power switch by the first driver stage if the signal indicative of the activation state of the second power switch indicates that the second power switch is de-activated;
and
a second driver control stage coupled to and configured to control the operation of the second driver stage, wherein the second driver control stage is further configured to delay the second activation command for activation of the second driver stage when a second control signal is asserted, to receive the signal indicative of an activation state of the first power switch, and to enable the activation of the second power switch by the second driver stage if the signal indicative of an activation state of the first power switch indicates that the first power switch is de-activated;
and
an output current sensing circuit coupled to the output terminal of the DC-DC switching converter and to the first and second driver control stages, the output current sensing circuit configured to sense a sign of an output current delivered by the DC-DC switching converter at the output terminal when in operation;
wherein the output current sensing circuit generates and feeds the first control signal to the first driver control stage, the first control signal being asserted when, during operation, the sensed sign of the output current delivered by the DC-DC switching converter at the output terminal is negative and the DC-DC switching converter is sinking current from the load;
wherein the output current sensing circuit generates and feeds the second control signal to the second driver control stage, the second control signal being asserted when, during operation, the sensed sign of the output current delivered by the DC-DC switching converter at the output terminal is positive and the DC-DC switching converter is sourcing current to the load;
wherein the first and second driver control stages control the operation of the first and second driver stages according to states of the first and second control signals to selectively delay activation of the first and second power switches depending on the sensed sign of the output current.

15 more elements

A DC-DC switching converter, comprising:

a first power switch operable to selectively couple an output terminal of the DC-DC switching converter to a first voltage, and a second power switch operable to selectively couple the output terminal to a second voltage;
a first driver stage coupled to and configured to control the first power switch, and a second driver stage coupled to and configured to control the second power switch;
wherein the first driver stage comprises a first switch, a second switch, and a third switch coupled in series between the first voltage and a first internal reference voltage, wherein the first switch is controlled by a drive command, the second switch is controlled by an activation command for the first driver stage and by a first signal indicative of a voltage level at the output terminal of the DC-DC switching converter, and the third switch is controlled by a switch control signal depending on the drive command and a signal indicative of an activation state of the second power switch;
a first driver control stage coupled to and configured to control the operation of the first driver stage, and a second driver control stage coupled to and configured to control the operation of the second driver stage, wherein the first driver control stage is configured to delay the activation command for the first driver stage when a first control signal is asserted;
and
an output current sensing circuit coupled to the output terminal of the DC-DC switching converter, the output current sensing circuit configured to:
sense a sign of an output current delivered by the DC-DC switching converter at the output terminal when in operation, and to generate control signals for the first and second driver control stages;
and
generate and feed the first control signal to the first driver control stage, the first control signal being asserted when, during operation, the sensed sign of the output current delivered by the DC-DC switching converter at the output terminal is negative and the DC-DC switching converter is sinking current from a load.

6 more elements

A DC-DC switching converter, comprising:

power switches operable to selectively couple an output terminal of the DC-DC switching converter to a first voltage or a second voltage, the output terminal being coupleable to a load when the DC-DC switching converter is in use;
a driver stage coupled to the power switches and configured to drive the power switches;
a driver control stage coupled to the driver stage and configured to control the operation of the driver stage;
and
an output current sensing circuit coupled to the output terminal of the DC-DC switching converter and to the driver control stage, the output current sensing circuit configured to sense a sign of an output current delivered by the DC-DC switching converter at the output terminal when in operation and to generate control signals for the driver control stage;
wherein the driver control stage controls the operation of the driver stage according to states of the control signals received from the output current sensing circuit to selectively delay activation of the power switches depending on the sensed sign of the output current;
wherein the power switches comprise:
a first power switch operable for selectively coupling the output terminal of the DC-DC switching converter to the first voltage;
and
a second power switch operable for selectively coupling the output terminal of the DC-DC switching converter to the second voltage;
wherein the driver stage comprises:
a first driver stage coupled to and configured to control the first power switch;
and
a second driver stage coupled to and configured to control the first power switch;
wherein the first driver stage comprises:
a first switch, a second switch, and a third switch in series between the first voltage and a first internal reference voltage of the DC-DC switching converter configured to cause the activation of the first power switch when applied thereto;
wherein the first switch is controlled by a first drive command fed to the driver control stage;
wherein the second switch is controlled by a first activation command for the activation of the first driver stage and by a first signal indicative of a voltage level at the output terminal of the DC-DC switching converter;
and
wherein the third switch is controlled by a first switch control signal depending on the first drive command and on a signal indicative of an activation state of the second power switch;
wherein the second driver stage comprises:
a fourth switch, a fifth switch and a sixth switch in series between the second voltage and a second internal reference voltage of the DC-DC switching converter configured to cause the activation of the second power switch when applied thereto;
wherein the fourth switch is controlled by a second drive command fed to the driver control stage;
wherein the fifth switch is controlled by a second activation command for the activation of the second driver stage and by a second signal indicative of a voltage level at the output terminal of the DC-DC switching converter;
and
wherein the sixth switch is controlled by a second switch control signal depending on the second drive command and on the signal indicative of an activation state of the second power switch.

23 more elements

Dependencies are inferred from the claim text.

Description9,151 words

Summary992 words

#This application claims the priority benefit of Italian Application for Patent No. 102020000028121, filed on Nov. 24, 2020, the content of which is hereby incorporated by reference in its entirety to the maximum extent allowable by law.

#The present disclosure generally relates to the field of switching converters. Particularly, the present disclosure relates to DC-DC switching converters, which are types of electronic power converters used for converting a direct current (DC) input voltage into a direct current (DC) output voltage of value generally different from the DC input voltage value, i.e., for converting a DC power source from one voltage level to another.

#DC-DC switching converters (also referred to as DC-DC power converters or DC-DC voltage regulators, and hereafter referred to as DC-DC converters) are a class of Switched-Mode Power Supply (SMPS) devices. DC-DC converters are often used in electronic systems comprising a DC power source (such as a battery) and one or more electronic/electro-mechanic components, each one operating at a respective voltage.

Brief description of the drawings17 figures

#The above features and advantages of the present disclosure, as well as additional features and advantages, will be made apparent by the following detailed description of exemplary embodiments thereof. For its better intelligibility, the following description should be read making reference to the annexed figures, wherein:

#FIG. 1A is a functional block diagram of a DC-DC converter in which an approach according to an embodiment of the present disclosure is implemented;

#FIG. 1B shows a possible use of the DC-DC converter of FIG. 1A;

Detailed description7,724 words

#FIG. 1A is a functional block diagram of a DC-DC converter in which an approach according to an embodiment of the present disclosure is implemented. In particular, the DC-DC converter depicted in FIG. 1A is a step-down switching regulator, particularly a buck converter.

#Without entering into excessive details not relevant for the understanding, the DC-DC converter of FIG. 1A, globally denoted as 100, has a power section that comprises a high side switch 105H and a low side switch 105L connected in series between a DC input voltage VIN and a DC reference voltage GND (power ground), which are externally supplied to the DC-DC converter 100. In an embodiment, the high side switch 105H comprises a p-MOS transistor (p-MOSFET) and the low side switch 105L comprises an n-MOS transistor (n-MOSFET), this circuitry referred to in the art as a p-n (half) bridge circuit. The p-MOSFET and the n-MOSFET are power MOSFETs, e.g., DMOS. The source terminal of the p-MOSFET 105H is coupled to the input voltage VIN, the drain terminal of the p-MOSFET 105H is coupled to the drain terminal of the n-MOSFET 105L, and the source terminal of the n-MOSFET 105L is coupled to the reference voltage GND. The drain terminal of the p-MOSFET 105H and the drain terminal of the n-MOSFET 105L are coupled to an output terminal or switching terminal LX of the DC-DC converter 100 (to which a load—not shown in the figure, can be connected).

#The gate terminals of the p-MOSFET 105H and the n-MOSFET 105L are controlled by a driver circuit 110, which, according to an embodiment here disclosed, also includes an anti-cross conduction circuit, as will described in detail herein. In an embodiment, the driver circuit 110 is also coupled to the output terminal LX of the DC-DC converter 100, for sensing a polarity of the output current of the DC-DC converter 100 (i.e., the current delivered to, or sunk from, a load connected to the output terminal LX).

Driver circuit for switching converters

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Driver circuit for switching converters

Life of this patent

Life of this patent

Abstract

Drawings

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Claims14

Description9,151 words

Drawings

Classification11 codes

Life of this patent

Description9,151 words