IEC 62680-3:2013

IEC 62680-3 ®
Edition 1.0 2013-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Universal serial bus interfaces for data and power –
Part 3: USB Battery Charging Specification, Revision 1.2

Interfaces de bus universel en série pour les données et l'alimentation
électrique –
Partie 3: Spécification de chargement des batteries USB, révision 1.2

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IEC 62680-3 ®
Edition 1.0 2013-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Universal serial bus interfaces for data and power –

Part 3: USB Battery Charging Specification, Revision 1.2

Interfaces de bus universel en série pour les données et l'alimentation

électrique –
Partie 3: Spécification de chargement des batteries USB, révision 1.2

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.220; 35.200 ISBN 978-2-8322-1049-9

– 2 – IEC 62680-3:2013
© USB-IF:2012
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
UNIVERSAL SERIAL BUS INTERFACES FOR DATA AND POWER –

Part 3: USB Battery Charging Specification, Revision 1.2

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
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International Standard IEC 62680-3 has been prepared by technical area 14: Interfaces and
methods of measurement for personal computing equipment, of IEC technical committee 100:
Audio, video and multimedia systems and equipment.
The text of this standard is based on documents prepared by the USB Implementers Forum
(USB-IF). The structure and editorial rules used in this publication reflect the practice of the
organization which submitted it.
The text of this standard is based on the following documents:
FDIS Report on voting
100/2157/FDIS 100/2190/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.

© USB-IF:2012
A list of all the parts in the IEC 62680 series, published under the general title Universal serial
bus interfaces for data and power can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 4 – IEC 62680-3:2013
© USB-IF:2012
INTRODUCTION
The IEC 62680 series is based on a series of specifications that were originally developed by
the USB Implementers Forum (USB-IF). These specifications were submitted to the IEC under
the auspices of a special agreement between the IEC and the USB-IF.
The USB Implementers Forum, Inc. (USB-IF) is a non-profit corporation founded by the group
of companies that developed the Universal Serial Bus specification. The USB-IF was formed
to provide a support organization and forum for the advancement and adoption of Universal
Serial Bus technology. The Forum facilitates the development of high-quality compatible USB
peripherals (devices), and promotes the benefits of USB and the quality of products that have
passed compliance testing.
ANY USB SPECIFICATIONS ARE PROVIDED TO YOU "AS IS, "WITH NO WARRANTIES
WHATSOEVER, INCLUDING ANY WARRANTY OF MERCHANTABILITY, NON-
INFRINGEMENT, OR FITNESS FOR ANY PARTICULAR PURPOSE. THE USB
IMPLEMENTERS FORUM AND THE AUTHORS OF ANY USB SPECIFICATIONS DISCLAIM
ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PROPRIETARY
RIGHTS, RELATING TO USE OR IMPLEMENTATION OR INFORMATION IN THIS
SPECIFICAITON.
THE PROVISION OF ANY USB SPECIFICATIONS TO YOU DOES NOT PROVIDE YOU
WITH ANY LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, TO ANY
INTELLECTUAL PROPERTY RIGHTS.
Entering into USB Adopters Agreements may, however, allow a signing company to
participate in a reciprocal, royalty-free licensing arrangement for compliant products. For
more information, please see:
http://www.usb.org/developers/docs/
http://www.usb.org/developers/devclass_docs#approved

IEC DOES NOT TAKE ANY POSITION AS TO WHETHER IT IS ADVISABLE FOR YOU TO
ENTER INTO ANY USB ADOPTERS AGREEMENTS OR TO PARTICIPATE IN THE USB
IMPLEMENTERS FORUM.”
This series covers the Universal Series Bus interfaces for data and power and consists of the
following parts:
IEC 62680-1, Universal Serial Bus interfaces for data and power - Part 1: Universal Serial Bus
Specification, Revision 2.0
IEC 62680-2, Universal Serial Bus interfaces for data and power - Part 2: USB Micro-USB
Cables and Connectors Specification, Revision 1.01

IEC 62680-3, Universal Serial Bus interfaces for data and power - Part 3: USB Battery
Charging Specification, Revision 1.2

IEC 62680-4, Universal Serial Bus interfaces for data and power - Part 4: Universal Serial Bus
Cables and Connectors Class Document Revision. 2.0
This part of the IEC 62680 series consists of several distinct parts:
• the main body of the text, which consists of the original specification and all ECN and
Errata developed by the USB-IF;

© USB-IF:2012
CONTENTS
1 Introduction . 12
1.1 Scope . 12
1.2 Background . 12
1.3 Reference Documents . 12
1.4 Definitions of Terms . 12
1.4.1 Accessory Charger Adaptor . 12
1.4.2 ACA-Dock . 13
1.4.3 Attach versus Connect . 13
1.4.4 Charging Downstream Port . 13
1.4.5 Charging Port . 13
1.4.6 Dead Battery Threshold . 13
1.4.7 Dedicated Charging Port . 13
1.4.8 Downstream Port . 14
1.4.9 Micro ACA . 14
1.4.10 Portable Device . 14
1.4.11 Rated Current . 14
1.4.12 Standard ACA . 14
1.4.13 Standard Downstream Port . 14
1.4.14 USB Charger . 14
1.4.15 Weak Battery Threshold . 14
1.5 Parameter Values . 14
1.6 OTG Considerations . 15
1.7 Super Speed Considerations . 15
2 Dead Battery Provision . 15
2.1 Background . 15
2.2 DBP – Unconfigured Clause . 15
2.3 DBP – Configured Clause . 16
3 Charging Port Detection . 17
3.1 Overview . 17
3.2 Charger Detection Hardware . 18
3.2.1 Overview . 18
3.2.2 VBUS Detect . 18
3.2.3 Data Contact Detect . 19
3.2.4 Primary Detection . 22
3.2.5 Secondary Detection. 29
3.2.6 ACA Detection . 32
3.3 Charger Detection Algorithms . 34
3.3.1 Weak Battery Algorithm . 34
3.3.2 Good Battery Algorithm . 35
3.4 Charger Detection Timing . 36
3.4.1 Data Contact Detect Timing . 36
3.4.2 Detection Timing, CDP . 39
3.5 Ground Current and Noise Margins . 40
4 Charging Port and Portable Device Requirements . 40
4.1 Charging Port Requirements . 40
4.1.1 Overshoot . 40
4.1.2 Maximum Current . 40

– 6 – IEC 62680-3:2013
© USB-IF:2012
4.1.3 Detection Renegotiation . 41
4.1.4 Shutdown Operation . 41
4.1.5 Failure Voltage . 41
4.1.6 Multiple Ports. 41
4.2 Charging Downstream Port . 41
4.2.1 Required Operating Range . 41
4.2.2 Shutdown Operation . 42
4.2.3 Undershoot . 42
4.2.4 Detection Signaling . 42
4.2.5 Connector . 43
4.3 ACA-Dock . 43
4.3.1 Required Operating Range . 43
4.3.2 Undershoot . 43
4.3.3 Detection Signaling . 43
4.3.4 Connector . 43
4.4 Dedicated Charging Port . 43
4.4.1 Required Operating Range . 43
4.4.2 Undershoot . 44
4.4.3 Detection Signaling . 44
4.4.4 Connector . 44
4.5 Accessory Charger Adapter . 45
4.5.1 Required Operating Range . 45
4.5.2 Undershoot . 45
4.5.3 Detection Signaling . 45
4.5.4 Connector . 45
4.6 Portable Device . 45
4.6.1 Allowed Operating Range . 45
4.6.2 Detection Signaling . 46
4.6.3 Detection Renegotiation . 46
4.6.4 Connector . 47
5 Parameter Values . 47
6 Accessory Charger Adapter . 50
6.1 Introduction . 50
6.2 Micro ACA . 52
6.2.1 Micro ACA Ports . 52
6.2.2 Micro ACA Connectivity Options . 53
6.2.3 Micro ACA Architecture . 54
6.2.4 Micro ACA Modes of Operation . 54
6.2.5 Implications of not Supporting Micro ACA Detection . 55
6.2.6 Micro ACA Requirements . 56
6.2.7 Portable Device State Diagram . 57
6.3 Standard ACA . 59
6.3.1 Standard ACA Ports . 59
6.3.2 Standard ACA Architecture . 60
6.3.3 Standard ACA Modes of Operation . 61
6.3.4 Implications of not Supporting Standard ACA Detection . 61
6.3.5 Standard ACA Requirements . 61

© USB-IF:2012
Battery Charging
Specification
(Including errata and ECNs through March 15, 2012)

Revision 1.2
March 15, 2012
All rights reserved.
A LICENSE IS HEREBY GRANTED TO REPRODUCE THIS SPECIFICATION FOR INTERNAL
USE ONLY. NO OTHER LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR
OTHERWISE, IS GRANTED OR INTENDED HEREBY.
USB-IF AND THE AUTHORS OF THIS SPECIFICATION EXPRESSLY DISCLAIM ALL
LIABILITY FOR INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS, RELATING TO
IMPLEMENTATION OF INFORMATION IN THIS SPECIFICATION. USB-IF AND THE
AUTHORS OF THIS SPECIFICATION ALSO DO NOT WARRANT OR REPRESENT THAT
SUCH IMPLEMENTATION(S) WILL NOT INFRINGE THE INTELLECTUAL PROPERTY
RIGHTS OF OTHERS.
THIS SPECIFICATION IS PROVIDED "AS IS” AND WITH NO WARRANTIES, EXPRESS OR
IMPLIED, STATUTORY OR OTHERWISE. ALL WARRANTIES ARE EXPRESSLY
DISCLAIMED. NO WARRANTY OF MERCHANTABILITY, NO WARRANTY OF NON-
INFRINGEMENT, NO WARRANTY OF FITNESS FOR ANY PARTICULAR PURPOSE, AND
NO WARRANTY ARISING OUT OF ANY PROPOSAL, SPECIFICATION, OR SAMPLE.
IN NO EVENT WILL USB-IF OR USB-IF MEMBERS BE LIABLE TO ANOTHER FOR THE
COST OF PROCURING SUBSTITUTE GOODS OR SERVICES, LOST PROFITS, LOSS OF
USE, LOSS OF DATA OR ANY INCIDENTAL, CONSEQUENTIAL, INDIRECT, OR SPECIAL
DAMAGES, WHETHER UNDER CONTRACT, TORT, WARRANTY, OR OTHERWISE,
ARISING IN ANY WAY OUT OF THE USE OF THIS SPECIFICATION, WHETHER OR NOT
SUCH PARTY HAD ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

– 8 – IEC 62680-3:2013
© USB-IF:2012
Contributors
Mark Lai Allion Test Labs
Sammy Mbanta Astec Power
Abel Astley Broadcom
Kenneth Ma Broadcom
Shimon Elkayam Broadcom
Gaurav Singh Cypress
Dan Ellis DisplayLink
Graham Connolly Fairchild
Oscar Freitas Fairchild
Joel Silverman Kawasaki
Pat Crowe MQP Electronics
Juha Heikkila Nokia
Richard Petrie Nokia
Sten Carlsen Nokia
Jeroen Kleinpenning NXP Semiconductors
Terry Remple, Chair Qualcomm
Dave Haglan SMSC
Mark Bohm SMSC
Morgan Monks SMSC
Tim Knowlton SMSC
Morten Christiansen ST Ericsson
Nicolas Florenchie ST Ericsson
Shaun Reemeyer ST Ericsson
George Paparrizos Summit Microelectronics
Adam Burns Synopsys
Wei Ming Telecommunication Metrology Center of MII
Jean Picard Texas Instruments
Ivo Huber Texas Instruments
Pasi Palojarvi Texas Instruments
Steven Tom Texas Instruments
Ed Beeman USB-IF
Mark Paxson USB-IF
© USB-IF:2012
Revision History
Revision Date Author Description
BC1.0 Mar 8, 2007 Terry Remple First release

BC1.1 April 15, 2009 Terry Remple Major updates to all sections. Added Data Contact
Detect protocol, and Accessory Charger Adapter.

BC1.2 Oct 5, 2010 Terry Remple Following items indicate changes from BC1.1 to BC1.2.
References below to Section, Figures and Tables refer
Adam Burns
to BC1.2, unless BC1.1 is specifically indicated.
1. Allow DCPs to output more than 1.5A. Allows
Portable Devices (PDs) with switch mode chargers to
draw more power. Section 4.4.1.
2. Increase minimum CDP current to 1.5A. Without
change, PDs had to draw less than 500mA, to avoid
CDP shutdown. Table 5-2.
3. Indicate that ICDP max and IDCP max limits of 5A
come from USB 2.0, and are safety limits. Table 5-2
note 1.
4. Allow PDs to draw up to 1.5A during HS chirp and
traffic. Remove previous limits of 560mA and 900mA
which was based on HS common mode ranges. Section
3.5.
5. Require CDPs to support 1.5A during HS chirp and
traffic. Affects CDP common mode range. Section 3.5.
6. Reduce maximum PD current from 1.8A to 1.5A, to
avoid shutdown when attached to CDP. Table 5-2.
7. Rename Docking Station to ACA-Dock, to avoid
confusion with other types of Docking Stations.
8. Require ACA-Dock to differentiate itself from an ACA,
by enabling VDM_SRC during no activity. Section
3.2.4.4.
9. Allow CDP to leave VDM_SRC enabled while
peripheral not connected. Section 3.2.4.2.
10. Remove ICHG_SHTDWN. This was a recommended
max output current for Charging Ports with VBUS
grounded. BC1.1 Section 4.1.
11. Require VDP_SRC to not pull D+ below 2.2V when
D+ is being pulled to VDP_UP through RDP_UP.
Require VDM_SRC to not pull D- below 2.2V when D- is
being pulled high. Required for ACA-Dock support.
Table 5-1 notes 1 and 2.
12. Make DCD current source optional for PDs. Section
3.2.3.
13. Make DCD timeout required for PDs. Section 3.2.3.
14. Make Secondary Detection optional for PDs. Section
4.6.2.
15. Make Good Battery Algorithm required behavior for
PDs. Section 3.2.4.
16. Remove resistive detection. BC1.1 Section 3.9.
17. Change PD Required Operating Range to include
4.5V at 500mA. Figure 4-3.
18. Allow any downstream port to act as a DCP. Section
4.1.3.
19. Require PDs to enable VDP_SRC or RDP_PU when
charging from a DCP. Section 3.3.2.
20. Allow chargers to renegotiate current with PD by
dropping and reasserting VBUS. Section 4.1.3.

– 10 – IEC 62680-3:2013
© USB-IF:2012
Revision Date Author Description
21. Require PDs to discharge their own VBUS input
after VBUS drops to support charger port renegotiation
request. Section 4.6.3.
22. Allow PDs to disconnect and repeat Charger
Detection multiple times while attached, with specified
timing. Section 4.6.3.
23. Reduce DCP input impedance between D+, D- to
VBUS and ground from 1MΩ to 300kΩ. Section 4.4.3.
24. Require CDPs to recover after over-current
condition. Section 4.2.2.
25. Allow greater DCP undershoot for large load current
steps, to enable low quiescent current chargers
required by Europe. Section 4.4.2.
26. Define ACAs and ACA-Docks as types of Charging
Ports. Section 1.4.5.
27. Use session valid voltage range defined in EH and
OTG Supplement rev 2.0. Section 3.2.2.
28. Only devices that can operate stand-alone from
internal battery power are allowed to use the Dead
Battery Provision. Section 2.2.
29. Allow compound PDs to draw ISUSP plus an
responsible for protecting themselves against higher
voltages on VBUS. BC1.1 Section 6.7.
45. Require ACAs to continue providing power to OTG
device from Charging Port, even if ground offsets or
USB reset cause D- to go below VDAT_REF. Section
6.2.6.
46. Change charger shutdown recovery time
(TSHTDWN_REC) from 2 seconds to 2 minutes. Table
5-5.
47. Indicate that ACA-Dock is required to pull D+ to
VDP_UP with RDP_UP when VBUS is asserted. Section
3.2.4.4.
48. Remove statements regarding devices with multiple
receptacles. Covered in Multiple Receptacle white
paper at http://www.usb.org/developers/docs/.
49. Improve readability by adding and updating
drawings, re-structuring sections, and clarifying text.
BC 1.2 Oct 12, 2011 Pat Crowe Includes errata changes from Oct 12, 2011
plus errata
BC 1.2 Mar 15, 2012 Pat Crowe Includes errata changes from Mar 15, 2012:
plus further
1. Corrections to Micro ACA specification.
errata
© USB-IF:2012
Acronyms
ACA Accessory Charger Adapter
CDP Charging Downstream Port
DBP Dead Battery Provision
DCD Data Contact Detect
DCP Dedicated Charging Port
FS Full Speed
HS High-Speed
LS Low-Speed
OTG On-The-Go
PC Personal Computer
PD Portable Device
PHY Physical Layer Interface for High-Speed USB
PS2 Personal System 2
SDP Standard Downstream Port
SRP Session Request Protocol
TPL Targeted Peripheral List
USB Universal Serial Bus
USBCV USB Command Verifier
USB-IF USB Implementers Forum
VBUS Voltage line of the USB interface

– 12 – IEC 62680-3:2013
© USB-IF:2012
1 Introduction
1.1 Scope
The Battery Charging Working Group is chartered with creating specifications that define
limits as well as detection, control and reporting mechanisms to permit devices to draw
current in excess of the USB 2.0 specification for charging and/or powering up from dedicated
chargers, hosts, hubs and charging downstream ports. These mechanisms are backward
compatible with USB 2.0 compliant hosts and peripherals.
1.2 Background
The USB ports on personal computers are convenient places for Portable Devices (PDs) to
draw current for charging their batteries. This convenience has led to the creation of USB
Chargers that simply expose a USB standard-A receptacle. This allows PDs to use the same
USB cable to charge from either a PC or from a USB Charger.
If a PD is attached to a USB host or hub, then the USB 2.0 specification requires that after
connecting, a PD must draw less than:
• 2.5 mA average if the bus is suspended
• 100 mA if bus is not suspended and not configured
• 500 mA if bus is not suspended and configured for 500 mA
If a PD is attached to a Charging Port, (i.e. CDP, DCP, ACA-Dock or ACA), then it is allowed
to draw IDEV_CHG without having to be configured or follow the rules of suspend.
In order for a PD to determine how much current it is allowed to draw from an upstream USB
port, there need to be mechanisms that allow the PD to distinguish between a Standard
Downstream Port and a Charging Port. This specification defines just such mechanisms.
Since PDs can be attached to USB chargers from various manufacturers, it is important that
all provide an acceptable user experience. This specification defines the requirements for a
compliant USB charger, which is referred to in this spec as a USB Charger.
If a PD has a Dead or Weak Battery, then the Connect Timing Engineering Change Notice
(ECN) issued by the USB-IF on the USB 2.0 spec allows that device to draw up to IUNIT while
attached but not connected. The conditions associated with this ECN are contained in
Section 2 of this specification, and are referred to as the Dead Battery Provision (DBP).
1.3 Reference Documents
The following specifications contain information relevant to the Battery Charging Specification.
• OTG and Embedded Host Supplement, Revision 2.0
• USB 2.0 Specification
• USB 3.0 Specification
1.4 Definitions of Terms
This section contains definitions for some of the terms used in this specification.
1.4.1 Accessory Charger Adaptor
An Accessory Charger Adaptor (ACA) is an adaptor which allows a single USB port to be
attached to both a charger and another device at the same time.

© USB-IF:2012
The following terminology is used when referring to an ACA:
• ACA-A An ACA with ID resistance of RID_A
• ACA-B An ACA with ID resistance of RID_B
• ACA-C An ACA with ID resistance of RID_C
See Section 6 for details on an ACA.
1.4.2 ACA-Dock
An ACA-Dock is a docking station that has one upstream port, and zero or more downstream
ports. The upstream port can be attached to a PD, and is capable of sourcing ICDP to the PD.
An ACA-Dock signals it is an ACA-Dock to the PD by enabling VDM_SRC during USB idle, and
by pulling ID to ground through a resistance of RID_A. See Section 3.2.4.4 for more details.
1.4.3 Attach versus Connect
This specification makes a distinction between the words “attach” and “connect”. A
downstream device is considered to be attached to an upstream port when there is a physical
cable between the two.
A downstream device is considered to be connected to an upstream port when it is attached
to the upstream port, and when the downstream device has pulled either the D+ or D- data
line high through a 1.5 kΩ resistor, in order to enter Low-Speed, Full-Speed or High-Speed
signaling.
1.4.4 Charging Downstream Port
A Charging Downstream Port (CDP) is a downstream port on a device that complies with the
USB 2.0 definition of a host or a hub, except that it shall support the Charging Downstream
Port features specified herein.
A CDP shall output a voltage of VDM_SRC on its D- line when it senses a voltage greater than
VDAT_REF but less than VLGC on its D+ line when not connected to a peripheral. A CDP shall
not output a voltage of VDM_SRC on its D- line from the time that the peripheral is connected,
to the time that the peripheral is disconnected.
1.4.5 Charging Port
A Charging Port is a DCP, CDP, ACA-Dock or ACA.
1.4.6 Dead Battery Threshold
The Dead Battery Threshold is defined as the maximum charge level of a battery such that
below this threshold, a device is assured of not being able to power up successfully.
A Dead Battery is defined as one that is below the Dead Battery Threshold.
1.4.7 Dedicated Charging Port
A Dedicated Charging Port (DCP) is a downstream port on a device that outputs power
through a USB connector, but is not capable of enumerating a downstream device. A DCP
shall source IDCP at an average voltage of VCHG.
A DCP shall short the D+ line to the D- line.

– 14 – IEC 62680-3:2013
© USB-IF:2012
1.4.8 Downstream Port
In this specification, a Downstream Port refers to either a Standard Downstream Port or a
Charging Downstream Port.
1.4.9 Micro ACA
A Micro ACA is an ACA with a Micro-AB receptacle on the Accessory Port.
1.4.10 Portable Device
A PD as used in this specification is a device which is compliant with this specification and the
USB 2.0 specification, and can draw charging current from USB.
1.4.11 Rated Current
The Rated Current of a Charging Port is the amount of current that a Charging Port can output
and still maintain a VBUS voltage of VCHG. The Rated Current of a DCP is required to be
within IDCP, and the rated current of a CDP or ACA-Dock is required to be within ICDP.
1.4.12 Standard ACA
A Standard ACA is an ACA with a Standard-A receptacle on the Accessory Port.
1.4.13 Standard Downstream Port
In this specification, a Standard Downstream Port (SDP) refers to a downstream port on a
device that complies with the USB 2.0 definition of a host or hub. An SDP expects a
downstream device with a good battery to draw less than 2.5 mA average when unconnected
or suspended, up to 100 mA maximum when connected and not configured and not
suspended, and up to 500 mA maximum if so configured and not suspended. A downstream
device can be enumerated when it is connected to an SDP.
An SDP pulls the D+ and D- lines to ground through two 15 kΩ (typical) resistors.
An SDP may have the ability to sense when a PD is driving the D+ line to VDP_SRC, and then
DP_SRC whenever
manage its power states accordingly. PDs are required to drive D+ to V
they draw more than ISUSP while attached but not connected, as described in the Dead
Battery Provision.
1.4.14 USB Charger
A USB Charger is a device with a DCP, such as a wall adapter or car power adapter.
1.4.15 Weak Battery Threshold
The Weak Battery Threshold is defined as the minimum charge level of a battery such that
above this threshold, a device is assured of being able to power up successfully.
A Weak Battery is defined as one that is above the Dead Battery Threshold and below the
Weak Battery Threshold. A device with a Weak Battery may or may not be able to power up a
device successfully.
A Good Battery is defined as one that is above the Weak Battery Threshold.
1.5 Parameter Values
Parameter names are used throughout this specification instead of parameter values. All
parameter values are found in Section 5.

© USB-IF:2012
1.6 OTG Considerations
A PD with a Dead Battery cannot differentiate between a PC and an OTG A-device. Thus, a
PD will treat both the same.
If an OTG A-device is connected to a PD with a dead battery, then the OTG A-device is under
no obligation to provide any more current than it normally would to any device on its Targeted
Peripheral List (TPL).
An OTG A-device is allowed to stop driving VBUS after a time of TA_WAIT_BCON (See OTG 2.0
Supplement for value) while waiting for the B-device to connect. Thus, a PD with a Dead
Battery may not have time for significant charging when attached to an OTG A-device, if it
does not connect.
1.7 Super Speed Considerations
SuperSpeed ports defined in USB 3.0 are allowed to implement the charger detection
mechanisms defined in this spec. When a PD detects it is attached to a SuperSpeed port,
then ICFG_MAX changes to 900mA, and IUNIT changes to 150mA.
2 Dead Battery Provision
2.1 Background
The USB 2.0 specification allows a downstream device to draw a suspend current of up to
ISUSP from a SDP when the device is not connected or when the bus is suspended. If the bus
is not suspended and the device is configured, then USB 2.0 allows a device to draw up to
ICFG_MAX, depending on the configuration the host enables.
This limit of only ISUSP when not connected can be problematic for PDs with a Dead Battery
or a Weak Battery. Some PDs require more than IUNIT for several seconds just to power up.
Thus, PDs with Dead Batteries or Weak Batteries may not be able to power up when attached
to an SDP if they can only draw ISUSP when not connected.
USB 2.0 allows a PD that is a compound device to draw ISUSP for each downstream port while
attached but not connected or during suspend.
2.2 DBP – Unconfigured Clause
A PD with a Dead or Weak Battery is allowed to draw IUNIT from a Downstream Port using the
DBP while not configured, providing it behaves as follows:
• Reduces current to ISUSP after timeout
• If PD is not ready to connect and be enumerated within TSVLD_CON_WKB after attach,
then it shall reduce its current to ISUSP
• Enables VDP_SRC when attached but not connected
• PD shall enable VDP_SRC within TDBP_ATT_VDPSRC of attach
• PD shall connect within TDBP_VDPSRC_CON of disabling VDP_SRC

– 16 – IEC 62680-3:2013
© USB-IF:2012
• Uses current to power up and enumerate, or reach Weak Battery Threshold and
enumerate, as soon as possible
• PD shall not use the DBP current to perform unrelated tasks, such as:
• Charging beyond the Weak Battery Threshold
• Making a phone call
• Playing a song, video or game
• Establishing a wireless connection
• Only devices that can operate stand-alone from internal battery power are allowed to
use the DBP.
• Passes inrush test
• PD with Dead or Weak Battery shall pass USB-IF compliance inrush test
The unconfigured state includes the time that the PD is attached and not connected, and the
time that the PD is connected and not configured. A PD enters the configured state by
receiving a SET_CONFIGURATION command from the host.
2.3 DBP – Configured Clause
A PD with a Dead or Weak Battery is allowed to draw its configured current, (which can be up
to ICFG_MAX), from a Standard Downstream Port using the Dead Battery Provision (DBP) while
configured, and not have to pass USBCV tests, providing it behaves as follows:
• Responds to received tokens
• PD shall respond to any tokens addressed to it, with either a NAK or any other valid
USB response
• Responds to USB reset
• Upon receipt of USB reset, a PD shall reduce its current to IUNIT. PD is allowed to
disconnect upon receiving a reset. While disconnected, PD is allowed to use the
DBP – Unconfigured Clause.
• Responds to USB suspend
• Upon receipt of USB suspend, PD shall either remain connected, and reduce its
current to ISUSP, or it shall disconnect. While disconnected, the PD is allowed to use
the DBP – Unconfigured Clause.
• Provides full USB functionality after timeout, or disconnects
• After a time of TDBP_FUL_FNCTN from attach, a PD shall either remain connected and
be able to pass USBCV, or it shall disconnect. While disconnected, the PD is allowed
to use the DBP – Unconfigured Clause.
• Uses current to reach Weak Battery Threshold and provide full USB functionality as soon
as possible
• PD shall not use the DBP current to perform unrelated tasks, such as:
• Charging beyond the Weak Battery Threshold
• Making a phone call
• Playing a song, video or game
• Establishing a wirel
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