DC-DC CONVERTER WITH A DYNAMICALLY ADAPTING LOAD-LINE

• US 20190109537A1
• Filed: 11/21/2018
• Published: 04/11/2019
• Est. Priority Date: 08/30/2017
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Ongaro, Fabio, Couleur, Michael
• Granted Patent: US 10,644,592 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/305 in the event of power-supply fluctuations
• CPC Class Codes: H02M 1/0045 Converters combining the concepts of switch-mode regulation and linear regulation, e.g. linear pre-regulator to switching converter, linear and switching converter in parallel, same converter or same transistor operating either in linear or switching mode
• CPC Class Codes: H02M 1/0048 Circuits or arrangements for reducing losses using snubbers H02M1/34
• CPC Class Codes: H02M 1/14 Arrangements for reducing ripples from dc input or output
• CPC Class Codes: H02M 3/155 using semiconductor devices only
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H03F 2200/129 there being a feedback over the complete amplifier
• CPC Class Codes: H03F 3/213 in integrated circuits
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

Systems, apparatuses, and methods for efficiently generating a stable output for a transient load for one or more components are described. In various embodiments, a power converter includes two feedback loops to separate the stability and the equivalent output resistance, which allows the bandwidth to increase. The first loop includes a compensator receiving an output current of an amplifier. Additionally, a first converter and a first current mirror generate a target current based on the output current of the amplifier. Based on the target current, multiple step-down converters generate an output voltage, which is returned to the amplifier through a resistor. The second loop includes a second converter with a first order series RC filter to reduce the second loop'"'"'s response time. A second current mirror receives current from the second converter and generates a dynamically adapting feedback current, which flows through the resistor in the first loop.

Claims

1-20. -20. (canceled)

21. A power converter comprising:

an amplifier configured to;

receive a reference voltage and a feedback voltage;

determine a voltage difference between the reference voltage and the feedback voltage; and

convey an output current based on the voltage difference; and

a compensator configured to;

receive the output current; and

generate a first voltage based on the output current; and

first circuitry configured to;

receive the first voltage from the compensator; and

generate an output voltage on an output node based at least in part on the first voltage.

22. The power converter as recited in claim 21, further comprising a converter configured to:

receive the first voltage from the compensator; and

generate a first reference current.

23. The power converter as recited in claim 22, further comprising a current mirror configured to:

receive the first reference current from the converter; and

generate a target current based on the first reference current.

24. The power converter as recited in claim 23, further comprising a plurality of step-down direct current to direct current (DC-DC) converters configured to:

receive the target current from the current mirror;

receive an input voltage; and

generate the output voltage on the output node as a fraction of the input voltage, wherein the fraction is based on a duty cycle within the plurality of step-down DC-DC converters.

25. The power converter as recited in claim 21, further comprising a resistor connected between the output node and an input of the amplifier receiving the feedback voltage.

26. The power converter as recited in claim 25, further comprising second circuitry configured to decrease a feedback current flowing through the resistor, in response to determining a difference between the output voltage and the reference voltage is decreasing.

27. The power converter as recited in claim 25, further comprising second circuitry configured to increase a feedback current flowing through the resistor, in response to determining a difference between the output voltage and the reference voltage is increasing.

28. The power converter as recited in claim 21, wherein the amplifier is an open-loop amplifier with no local feedback to provide stability.

29. The power converter as recited in claim 28, wherein the compensator is a Type II compensator for the amplifier.

30. A method comprising:

receiving, by an amplifier, a reference voltage and a feedback voltage;

determining, by the amplifier, a voltage difference between the reference voltage and the feedback voltage;

conveying, by the amplifier, an output current based on the voltage difference;

generating, by a compensator, a first voltage based on the output current; and

generating, by the first circuitry, an output voltage on an output node based at least in part on the first voltage.

31. The method as recited in claim 30, further comprising:

receiving, by a converter, the first voltage from the compensator; and

generating, by the converter, a first reference current.

32. The method as recited in claim 31, further comprising:

receiving, by a current mirror, the first reference current from the converter; and

generating, by the current mirror, a target current based on the first reference current.

33. The method as recited in claim 32, further comprising:

receiving, by a plurality of step-down direct current to direct current (DC-DC) converters, the target current from the current mirror;

receiving, by the plurality of step-down DC-DC converters, an input voltage; and

generating, by the plurality of step-down DC-DC converters, the output voltage on the output node as a fraction of the input voltage, wherein the fraction is based on a duty cycle within the plurality of step-down DC-DC converters.

34. The method as recited in claim 30, further comprising connecting, by a resistor, the output node and an input of the amplifier receiving the feedback voltage.

35. The method as recited in claim 34, further comprising decreasing, by second circuitry, a feedback current flowing through the resistor, in response to determining a difference between the output voltage and the reference voltage is decreasing.

36. The method as recited in claim 30, wherein the amplifier is an open-loop amplifier with no local feedback to provide stability.

37. A system on a chip comprising:

a primary converter configured to convert an external voltage to an internal voltage;

a plurality of functional units; and

a power converter configured to generate an output voltage based on at least the internal voltage to one or more of the plurality of functional units, wherein the power converter comprises;

an amplifier configured to;

receive a reference voltage and a feedback voltage;

determine a voltage difference between the reference voltage and the feedback voltage; and

convey an output current based on the voltage difference; and

a compensator configured to;

receive the output current; and

generate a first voltage based on the output current; and

first circuitry configured to;

receive the first voltage from the compensator; and

generate an output voltage on an output node based at least in part on the first voltage.

38. The system on a chip as recited in claim 37, further comprising a converter configured to:

receive the first voltage from the compensator; and

generate a first reference current.

39. The system on a chip as recited in claim 38, further comprising a current mirror configured to:

receive the first reference current from the converter; and

generate a target current based on the first reference current.

40. The system on a chip as recited in claim 39, further comprising a plurality of step-down direct current to direct current (DC-DC) converters configured to:

receive the target current from the current mirror;

receive an input voltage; and

generate the output voltage on the output node as a fraction of the input voltage, wherein the fraction is based on a duty cycle within the plurality of step-down DC-DC converters.