WO2022035554A1

WO2022035554A1 - Power supply architecture with bidirectional battery idealization

Info

Publication number: WO2022035554A1
Application number: PCT/US2021/041918
Authority: WO
Inventors: Hasnain AKRAM; Ivan Perry; Eric J. King
Original assignee: Cirrus Logic International Semiconductor Ltd
Current assignee: Cirrus Logic International Semiconductor Ltd
Priority date: 2020-08-14
Filing date: 2021-07-16
Publication date: 2022-02-17
Anticipated expiration: 2023-02-14
Also published as: CN116210134A; GB2612487A; US20220052540A1; GB202300948D0; US11855471B2; US12184110B2; US20240072559A1

Abstract

A power management system (1) for use in a device comprising a battery (22) and one or more components (18) configured to draw electrical energy from the battery may include a first power converter (10) configured to electrically couple between charging circuity (16) configured to provide electrical energy for charging the battery (22) and the one or more downstream components (18) and a bidirectional power converter (20A) configured to electrically couple between the charging circuitry and the battery, wherein the bidirectional power converter is configured to transfer charge from the battery or transfer charge from the battery based on a power requirement of the one or more components and a power available from the first power converter.

Description

POWER SUPPLY ARCHITECTURE WITH BIDIRECTIONAL BATTERY IDEALIZATION

RELATED APPLICATION The present disclosure claims priority to United States Provisional Patent

Application Serial No. 63/065,759, filed August 14, 2020, and United States Provisional Patent Application Serial No. 63/148,352, filed February 11, 2021, both of which are incorporated by reference herein in their entirety. HELD OF DISCLOSURE

The present disclosure relates in general to circuits for electronic devices, including without limitation personal audio devices such as wireless telephones and media players, and more specifically, a power supply architecture with bidirectional battery idealization.

BACKGROUND

Portable electronic devices, including wireless telephones, such as mobile/cellular telephones, tablets, cordless telephones, mp3 players, smart watches, health monitors, and other consumer devices, are in widespread use. Such a portable electronic device may include circuitry for implementing a boost converter for converting a battery voltage (e.g., provided by a lithium-ion battery) into a supply voltage delivered to one or more components of the portable electronic device. The power delivery network may also regulate such supply voltage, and isolate the downstream loads of these one or more devices from fluctuation in an output voltage of the battery over the course of operation.

SUMMARY

In accordance with the teachings of the present disclosure, one or more disadvantages and problems associated with existing approaches to power supply architectures may be reduced or eliminated.

In accordance with embodiments of the present disclosure, a power management system for use in a device comprising a battery and one or more components configured to draw electrical energy from the battery may include a first power converter configured to electrically couple between charging circuity configured to provide electrical energy for charging the battery and the one or more downstream components, and a bidirectional power converter configured to electrically couple between the charging circuitry and the battery, wherein the bidirectional power converter is configured to transfer charge from the battery or transfer charge from the battery based on a power requirement of the one or more components and a power available from the first power converter.

In accordance with these and other embodiments of the present disclosure, a method may include, in a device comprising a battery and one or more components configured to draw electrical energy from the battery receiving electrical energy from charging circuity configured to provide electrical energy for charging the battery at a first power converter configured to electrically couple between the charging circuity and the one or more downstream components. The method may also include transferring charge from the battery or transferring charge from the battery, by a bidirectional power converter configured to electrically couple between the charging circuitry and the battery, based on a power requirement of the one or more components and a power available from the first power converter.

In accordance with these and other embodiments of the present disclosure, a method may include, a device may include a battery, one or more components configured to draw electrical energy from the battery, and a power management system. The power management system may include a first power converter configured to electrically couple between charging circuity configured to provide electrical energy for charging the battery and the one or more downstream components, and a bidirectional power converter configured to electrically couple between the charging circuitry and the battery, wherein the bidirectional power converter is configured to transfer charge from the battery or transfer charge from the battery based on a power requirement of the one or more components and a power available from the first power converter.

Technical advantages of the present disclosure may be readily apparent to one skilled in the art from the figures, description and claims included herein. The objects and advantages of the embodiments will be realized and achieved at least by the elements, features, and combinations particularly pointed out in the claims.

It is to be understood that both the foregoing general description and the following detailed description are examples and explanatory and are not restrictive of the claims set forth in this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present embodiments and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features, and wherein:

FIGURE 1 illustrates an example portable electronic device, in accordance with embodiments of the present disclosure;

FIGURE 2 illustrates a block diagram of selected components internal to a portable electronic device, in accordance with embodiments of the present disclosure;

FIGURE 3 illustrates a block diagram of selected components of an example power converter, in accordance with embodiments of the present disclosure;

FIGURE 4 illustrates a block diagram of selected components internal to a portable electronic device in an alternate embodiment of a portable electronic device, in accordance with embodiments of the present disclosure; and

FIGURE 5 illustrates a block diagram of selected components of another example power converter, in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION

FIGURE 1 illustrates an example portable electronic device 1, in accordance with embodiments of the present disclosure. FIGURE 1 depicts portable electronic device 1 coupled to a headset 3 in the form of a pair of earbud speakers 8 A and 8B. Headset 3 depicted in FIGURE 1 is merely an example, and it is understood that portable electronic device 1 may be used in connection with a variety of audio transducers, including without limitation, headphones, earbuds, in-ear earphones, and external speakers. A plug 4 may provide for connection of headset 3 to an electrical terminal of portable electronic device 1. Portable electronic device 1 may provide a display to a user and receive user input using a touch screen 2, or alternatively, a standard liquid crystal display (LCD) may be combined with various buttons, sliders, and/or dials disposed on the face and/or sides of portable electronic device 1.

FIGURE 2 illustrates a block diagram of selected components integral to portable electronic device 1, in accordance with embodiments of the present disclosure. As shown in FIGURE 2, portable electronic device 1 may include a battery charger 16, a power converter 10, a battery 22, a power converter 20A, and one or more downstream components 18.

Battery charger 16 may include any system, device, or apparatus configured to charge a battery, for example by delivering electrical energy to a battery in order that such battery converts the electrical energy to chemical energy that is stored in such battery. In some embodiments, battery charger 16 may include a wired charger configured to draw electrical energy from an electrical power outlet or from a power bank. In other embodiments, battery charger 16 may include a wireless charger configured to draw electrical energy via inductive coupling from a wireless charging pad or similar device. In some embodiments, a portable electronic device 1 may include both a wired charger and a wireless charger.

Power converter 10 may include any system, device, or apparatus configured to receive a charger voltage VCHARGE (e.g., 5 volts, 9 volts, 20 volts) output by battery charger convert such charger voltage VCHARGE into a supply voltage VSUPPLY (e.g., 5 volts). In some embodiments, power converter 10 may comprise a buck converter that may convert charger voltage VCHARGE into supply voltage VSUPPLY equal to or less than charger voltage VCHARGE. In these and other embodiments, power converter 10 may comprise a capacitive power converter or “charge pump.” In other embodiments, power converter 10 may comprise an inductor-based power converter.

Battery 22 may include any system, device, or apparatus configured to convert chemical energy stored within battery 22 to electrical energy for powering downstream components 18 of portable electronic device 1. Further, battery 22 may also be configured to recharge, in which it may convert electrical energy received by battery 22 into chemical energy to be stored for later conversion back into electrical energy. For example, in some embodiments, battery 22 may comprise a lithium-ion battery.

Power converter 20A may include any system, device, or apparatus configured to operate in a boost mode to receive battery voltage VBAT generated by battery 22 and convert such battery voltage VBAT into supply voltage VSUPPLY greater than or equal to battery voltage VBAT. In addition, as described in greater detail below, power converter 20A may also operate bidirectionally, including a buck mode in which power converter 20A may convert supply voltage VSUPPLY into battery voltage VBAT lesser than or equal to supply voltage VSUPPLY in order to recharge battery 22.

Downstream components 18 of portable electronic device 1 may include any suitable functional circuits or devices of portable electronic device 1, including without limitation processors, audio coder/decoders, amplifiers, display devices, etc. As shown in FIGURE 2, downstream components 18 may be powered from supply voltage VSUPPLY generated by either or both of power converter 10 and power converter 20 A.

FIGURE 3 illustrates a block diagram of selected components of an example power converter 20A, in accordance with embodiments of the present disclosure. Power converter 20A may be used to implement power converter 20A depicted in FIGURE 2.

As shown in FIGURE 3, power converter 20A may include a plurality of inductive phases 24 (e.g., phases 24A and 24B). As shown in FIGURE 3, each inductive phase 24 may include a power inductor 32, a first switch 34, and a second switch 36. Although FIGURE 3 depicts only two inductive phases 24 for the purposes of clarity and exposition, in some embodiments, power converter 20 A may have a single inductive phase 24 or may have more than two inductive phases 24. In operation in a boost mode, control circuitry 30 may periodically commutate first switches 34 (e.g., during a charging state of an inductive phase 24) and second switches 36 (e.g., during a transfer state of an inductive phase 24) of an inductive phase 24 by generating appropriate control signals Pi, Pi , P2, and P2 , to boost battery voltage VBAT to a higher supply voltage VSUPPLY at output capacitor 38 in order to regulate supply voltage VSUPPLY at a desired voltage level.

In addition, in operation in a buck mode, control circuitry 30 may periodically commutate second switches 36 (e.g., during a charging state of an inductive phase 24) and first switches 34 (e.g., during a transfer state of an inductive phase 24) of an inductive phase 24 by generating appropriate control signals Pi, Pi , P2, and P2 , to buck supply voltage VSUPPLY to a lower battery voltage VBAT in order to charge a battery (e.g. battery 22) regulate supply voltage VSUPPLY at a desired voltage level.

Accordingly, control circuitry 30 may sense charger voltage VCHARGE, battery voltage VBAT, supply voltage VSUPPLY, and/or another suitable parameter associated with portable electronic device 1 and based thereon, determine in which mode it is to operate, and then operate in such mode. For example, when power available from battery charger 16 and power converter 10 is in excess of a power demanded by downstream components 18, control circuitry 30 may operate power converter 20 A in the buck mode to deliver such excess power to battery 22. As another example, when power available from battery charger 16 and power converter 10 is insufficient to supply the power demanded by downstream components 18, control circuitry 30 may operate power converter 20A in the boost mode to draw power from battery 22.

Using such a power supply architecture such as that described above, in which an output of a charger path (e.g., battery charger 16 and power converter 10) is coupled to supply voltage VSUPPLY, power converter 20A may boost to downstream components 18 during discharge of battery 22 and buck to battery 22 during charging of battery 22. The flexibility of placing bidirectional power converter 20A between the electrical nodes for supply voltage VSUPPLY and battery voltage VBAT as described above is that it may provide an ideal fixed voltage of supply voltage VSUPPLY for both downstream components 18 and for the charger path (e.g., battery charger 16 and power converter 10), thus presenting an idealized version of battery behavior to both downstream components 18 and the charger path. Because power converter 20A may idealize battery 22 both during charging and discharge, power converter 20A may be able to handle power distribution in complex scenarios such as that which may occur when power demanded by downstream components 18 exceeds that available from the charger path.

FIGURE 4 illustrates a block diagram of selected components internal to portable electronic device 1 in an alternate embodiment IB of portable electronic device 1, in accordance with embodiments of the present disclosure. In alternate embodiment IB, instead of power converter 10 directly generating supply voltage VSUPPLY, power converter 10 may generate intermediate supply voltage VSUPPLY', which may be received by power converter 20B as an input. Also as shown in FIGURE 4, power converter 20B may be used in lieu of power converter 20A.

FIGURE 5 illustrates a block diagram of selected components of example power converter 20B, in accordance with embodiments of the present disclosure. Power converter 20B may be similar in many respects to power converter 20A, except that in power converter 20B, the node for intermediate supply voltage VSUPPLY' may be coupled to the boost output of at least one inductive phase 24A, the node for supply voltage VSUPPLY may be coupled to the boost output of at least one inductive phase 24B, and a bypass switch 40 may be interfaced between the nodes for intermediate supply voltage VSUPPLY' and supply voltage VSUPPLY-

In the embodiments represented by FIGURES 4 and 5, when battery 22 has insufficient state of charge, it may not be possible to boost from battery 22 at a high enough voltage to match intermediate supply voltage VSUPPLY' generated by power converter 10. Thus, in the case of portable electronic device 1 in which the output of power converter 10 is coupled to the boost output of power converter 20A, the resultant difference in voltages generated by power converter 10 and power converter 20A may cause an uncontrolled current to flow from the charger path (e.g., battery charger 16 and power converter 10).

To overcome this problem, control circuitry 30 may control bypass switch 40 in either a bypass mode or split mode of power converter 20B. In the bypass mode, power converter 20B may operate as a single multiphase buck or boost converter (e.g., in either of the boost mode or buck mode as described above with respect to power converter 20A). In the split mode, which may be activated when battery 22 is low on state of charge, power converter 20B may be effectively split into two separate converters to allow bucking down from intermediate supply voltage VSUPPLY' to battery voltage VBAT (in order to charge battery 22) and then boosting battery voltage VBAT up to at least a minimum voltage level for supply voltage VSUPPLY. Thus, power converter 20B may be able to operate in the boost mode in situations in which state of charge of battery 22 is insufficient to support boosting to higher voltages. Operating supply voltage VSUPPLY at a lower voltage may reduce current demands by downstream components 18.

As used herein, when two or more elements are referred to as “coupled” to one another, such term indicates that such two or more elements are in electronic communication or mechanical communication, as applicable, whether connected indirectly or directly, with or without intervening elements.

This disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the example embodiments herein that a person having ordinary skill in the art would comprehend. Similarly, where appropriate, the appended claims encompass all changes, substitutions, variations, alterations, and modifications to the example embodiments herein that a person having ordinary skill in the art would comprehend. Moreover, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, or component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative. Accordingly, modifications, additions, or omissions may be made to the systems, apparatuses, and methods described herein without departing from the scope of the disclosure. For example, the components of the systems and apparatuses may be integrated or separated. Moreover, the operations of the systems and apparatuses disclosed herein may be performed by more, fewer, or other components and the methods described may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order. As used in this document, “each” refers to each member of a set or each member of a subset of a set.

Although exemplary embodiments are illustrated in the figures and described below, the principles of the present disclosure may be implemented using any number of techniques, whether currently known or not. The present disclosure should in no way be limited to the exemplary implementations and techniques illustrated in the drawings and described above.

Unless otherwise specifically noted, articles depicted in the drawings are not necessarily drawn to scale.

All examples and conditional language recited herein are intended for pedagogical objects to aid the reader in understanding the disclosure and the concepts contributed by the inventor to furthering the art, and are construed as being without limitation to such specifically recited examples and conditions. Although embodiments of the present disclosure have been described in detail, it should be understood that various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the disclosure.

Although specific advantages have been enumerated above, various embodiments may include some, none, or all of the enumerated advantages. Additionally, other technical advantages may become readily apparent to one of ordinary skill in the art after review of the foregoing figures and description.

To aid the Patent Office and any readers of any patent issued on this application in interpreting the claims appended hereto, applicants wish to note that they do not intend any of the appended claims or claim elements to invoke 35 U.S.C. § 112(f) unless the words “means for” or “step for” are explicitly used in the particular claim.

Claims

WHAT IS CLAIMED IS:

1. A power management system for use in a device comprising a battery and one or more components configured to draw electrical energy from the battery, the power management system comprising: a first power converter configured to electrically couple between charging circuity configured to provide electrical energy for charging the battery and the one or more components; and a bidirectional power converter configured to electrically couple between the charging circuitry and the battery, wherein the bidirectional power converter is configured to transfer charge from the battery or transfer charge from the battery based on a power requirement of the one or more components and a power available from the first power converter.

2. The power management system of Claim 1 , wherein the bidirectional power converter is configured to: operate in a first mode to transfer charge to the battery when the power requirement is lesser than the power available from the first power converter; and operate in a second mode to transfer charge from the battery when the power requirement is greater than the power available from the first power converter.

3. The power management system of Claim 2, wherein the bidirectional power converter is configured to: operate as a buck converter in the first mode; and operate as a boost converter in the second mode.

4. The power management system of Claim 1 , wherein the bidirectional power converter is configured to operate in a plurality of modes including: a bypass mode, in which the bidirectional power converter operates as a single multiphase power converter; and a split mode, in which the bidirectional power converter operates as two separate power converters.

5. The power management system of Claim 4, wherein the two separate power converters comprise a buck converter and a boost converter.

6. The power management system of Claim 5, wherein: the buck converter converts a charging voltage generated by the charging circuitry to battery voltage for charging the battery; and the boost converter converts the battery voltage to a supply voltage for powering the one or more components.

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7. A method comprising, in a device comprising a battery and one or more components configured to draw electrical energy from the battery: receiving electrical energy from charging circuity configured to provide electrical energy for charging the battery at a first power converter configured to electrically couple between the charging circuity and the one or more components; and transferring charge from the battery or transferring charge from the battery, by a bidirectional power converter configured to electrically couple between the charging circuitry and the battery, based on a power requirement of the one or more components and a power available from the first power converter.

8. The method of Claim 7, further comprising: operating the bidirectional power converter in a first mode to transfer charge to the battery when the power requirement is lesser than the power available from the first power converter; and operating the bidirectional power converter in a second mode to transfer charge from the battery when the power requirement is greater than the power available from the first power converter.

9. The method of Claim 8, further comprising: operating the bidirectional power converter as a buck converter in the first mode; and operating the bidirectional power converter as a boost converter in the second mode.

10. The method of Claim 7, further comprising operating the bidirectional power converter in a plurality of modes including: a bypass mode, in which the bidirectional power converter operates as a single multiphase power converter; and a split mode, in which the bidirectional power converter operates as two separate power converters.

11. The method of Claim 10, wherein the two separate power converters comprise a buck converter and a boost converter. 15

12. The method of Claim 11, wherein: the buck converter converts a charging voltage generated by the charging circuitry to battery voltage for charging the battery; and the boost converter converts the battery voltage to a supply voltage for powering the one or more components.

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13. A device comprising a battery; one or more components configured to draw electrical energy from the battery; and a power management system comprising: a first power converter configured to electrically couple between charging circuity configured to provide electrical energy for charging the battery and the one or more components; and a bidirectional power converter configured to electrically couple between the charging circuitry and the battery, wherein the bidirectional power converter is configured to transfer charge from the battery or transfer charge from the battery based on a power requirement of the one or more components and a power available from the first power converter.

14. The device of Claim 13, wherein the bidirectional power converter is configured to: operate in a first mode to transfer charge to the battery when the power requirement is lesser than the power available from the first power converter; and operate in a second mode to transfer charge from the battery when the power requirement is greater than the power available from the first power converter.

15. The device of Claim 14, wherein the bidirectional power converter is configured to: operate as a buck converter in the first mode; and operate as a boost converter in the second mode.

16. The device of Claim 13, wherein the bidirectional power converter is configured to operate in a plurality of modes including: a bypass mode, in which the bidirectional power converter operates as a single multiphase power converter; and a split mode, in which the bidirectional power converter operates as two separate power converters. 17

17. The device of Claim 16, wherein the two separate power converters comprise a buck converter and a boost converter.

18. The device of Claim 17, wherein: the buck converter converts a charging voltage generated by the charging circuitry to battery voltage for charging the battery; and the boost converter converts the battery voltage to a supply voltage for powering the one or more components.