Voltage- and current-based control of direct current (DC)-DC converter

Patent metadata

Field	Value
Publication number	US-10938304-B2
Application number	US-201916447699-A
Country	US
Kind code	B2
Filing date	Jun 20, 2019
Priority date	Jun 20, 2019
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

Various embodiments provide a direct current (DC)-DC converter circuit. The DC-DC converter circuit includes a control circuit to switch the DC-DC converter circuit between a charge state, a discharge state, and a tri-state mode. As part of a first control loop, the control circuit may switch the DC-DC converter between the charge state and the discharge state based on the output voltage to provide the output voltage with the target voltage level. Additionally, as part of a second control loop, the control circuit may switch the DC-DC converter between the charge state and the discharge state based on the current through an inductor of the DC-DC converter. The second control loop may provide overcurrent protection for the DC-DC converter. Other embodiments may be described and claimed.

First claim

What is claimed is:

1. A direct current (DC)-DC converter circuit comprising:
an output stage to provide a regulated output voltage at an output node, wherein the output stage includes an inductor, and wherein the DC-DC converter circuit is operable in a first state in which the output node is coupled to a supply rail via the inductor, a second state in which the output node is coupled to a ground terminal via the inductor, and a third state in which the output node is uncoupled from the supply rail and the ground terminal via the inductor of the output stage; and
a control circuit coupled to the output stage, the control circuit to:
as part of a first control loop:
switch the DC-DC converter circuit from the first state to the second state responsive to a determination that the regulated output voltage is greater than a first voltage threshold;
switch the DC-DC converter circuit from the second state to the first state responsive to a determination that the regulated output voltage is less than a second voltage threshold; and
switch the DC-DC converter from the second state to the third state responsive to a determination that the inductor current reaches zero;

as part of a second control loop:
switch the DC-DC converter circuit from the first state to the second state responsive to a determination that the inductor current through the inductor is greater than a first current threshold; and
switch the DC-DC converter circuit from the second state to the first state responsive to a determination that the inductor current is less than a second current threshold, wherein the first and second current thresholds are positive and non-zero values, and wherein the first current threshold is greater than the second current threshold.

2. The DC-DC converter circuit of claim 1 , wherein, as part of the first control loop, the control circuit is to switch the DC-DC converter circuit from the first state to the second state based on the determination that the regulated output voltage is greater than the first voltage threshold and a determination that the inductor current is greater than a minimum current threshold, wherein the minimum current threshold is positive, non-zero, and less than the first and second current thresholds.

3. The DC-DC converter circuit of claim 1 , wherein the determination that the regulated output voltage is less than the second voltage threshold is a first determination, and wherein the control circuit is further to:
switch the DC-DC converter from the third state to the first state based on a second determination that the regulated output voltage is less than the second voltage threshold, wherein the second determination is different than the first determination.

4. The DC-DC converter circuit of claim 1 , wherein the first voltage threshold is the same as the second voltage threshold.

5. The DC-DC converter circuit of claim 1 , wherein the inductor is coupled between the output node and an internal node, and wherein the output stage further includes:
a pull-up transistor coupled between the internal node and the supply rail; and
a pull-down transistor coupled between the internal node and the ground terminal;
wherein:
when the DC-DC converter circuit is in the first state, the pull-up transistor is on and the pull-down transistor is off; and
when the DC-DC converter circuit is in the second state, the pull-up transistor is off and the pull-down transistor is on.

6. The DC-DC converter circuit of claim 1 , wherein the control circuit is to dynamically adjust the first voltage threshold to adjust a target voltage level of the regulated output voltage.

7. The DC-DC converter circuit of claim 1 , wherein the DC-DC converter is to provide the regulated output voltage to a circuit block at the output node, wherein the circuit block is to use the regulated output voltage as a power supply, and wherein the circuit block is on a same integrated circuit die as the DC-DC converter circuit.

8. A circuit comprising:
a direct current (DC)-DC converter that is to generate an output voltage at an output node, wherein the DC-DC converter includes:
an inductor coupled between the output node and an intermediate node;
a pull-up transistor coupled between the intermediate node and a supply rail that is to receive a supply voltage; and
a pull-down transistor coupled between the intermediate node and a ground terminal, wherein the DC-DC converter is operable in a first state in which the pull-up transistor is on and the pull-down transistor is off, a second state in which the pull-up transistor is off and the pull-down transistor is on, and a third state in which the pull-up transistor is off and the pull-down transistor is off; and
a control circuit to:
switch the DC-DC converter from the first state to the second state responsive to a determination that the output voltage is greater than a voltage threshold and an inductor current through the inductor is greater than a minimum current threshold, wherein the minimum current threshold is positive and non-zero;
switch the DC-DC converter from the first state to the second state responsive to a determination that the inductor current through the inductor is greater than a first current threshold, wherein the first current threshold is greater than the minimum current threshold;
switch the DC-DC converter from the second state to the first state responsive to a determination that the inductor current is less than a second current threshold, wherein the second current threshold is greater than the minimum current threshold and less than the first current threshold; and
switch the DC-DC converter from the second state to the third state responsive to a determination that the inductor current reaches zero.

9. The circuit of claim 8 , wherein the voltage threshold is a first voltage threshold, and wherein the control circuit is further to switch the DC-DC converter from the second state to the first state responsive to a determination that the output voltage is less than a second voltage threshold.

10. The circuit of claim 9 , wherein the first voltage threshold is the same as the second voltage threshold.

11. The circuit of claim 8 , wherein the control circuit is further to switch the DC-DC converter from the third state to the first state based on a determination that the output voltage is less than the voltage threshold or another voltage threshold.

12. The circuit of claim 8 , wherein the control circuit is to dynamically adjust the voltage threshold to adjust a target voltage level of the output voltage.

13. The circuit of claim 8 , further comprising a circuit block coupled to the output node to receive the output voltage and use the output voltage as a power supply.

14. A computing system comprising:
a motherboard; and
an integrated circuit die mounted to the motherboard, the integrated circuit die comprising:
a circuit block;
a voltage regulator to provide a regulated output voltage to the circuit block at an output node, the voltage regulator including:
an output stage that includes an inductor coupled to the output node, wherein the voltage regulator is operable in a charge state in which an inductor current provided to the output node through the inductor is to increase, a discharge state in which the inductor current is to decrease, and a tri-state mode in which the inductor current is zero; and
a control circuit coupled to the output stage, the control circuit to, as part of a first control loop:
switch the voltage regulator from the charge state to the discharge state responsive to a determination that the regulated output voltage is greater than a vo

Assignees

• Intel Corp

Inventors

• Herbison David
• Hesener Marc
• Werth Tobias
• Guenther Stefan

Classifications

• H02M1/0032

  Control circuits allowing low power mode operation, e.g. in standby mode · CPC title

• H02H7/1213

  for DC-DC converters · CPC title

• H02M1/32

  Means for protecting converters other than automatic disconnection · CPC title

• H02M3/156 Primary

  with automatic control of output voltage or current, e.g. switching regulators · CPC title

• G06F1/26

  Power supply means, e.g. regulation thereof (for memories G11C) · CPC title