IEC 63563-5:2025

Qi Specification version 2.0 - Part 5: Communications Physical Layer

IEC 63563-5:2025 defines the low-level (physical layer and the data link layer) formats of data bits, data bytes, and data packets. In addition, it provides requirements and guidelines for load modulation and frequency-shift keying.

General Information

• Status: Published
• Publication Date: 09-Feb-2025
• ICS: 29.240.99 - Other equipment related to power transmission and distribution networks
• ICS: 35.240.99 - IT applications in other fields
• Technical Committee: TA 15 - Wireless Power Transfer
• Drafting Committee: WG 1 - TC 100/TA 15/WG 1
• Current Stage: PRVD - Preparation of RVD
• Start Date: 17-Jan-2025
• Due Date: 17-Jan-2025
• Completion Date: 17-Jan-2025

Standards Content (Sample)

IEC 63563-5 ®
Edition 1.0 2025-02
INTERNATIONAL
STANDARD
Qi Specification version 2.0 –
Part 5: Communications Physical Layer

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IEC 63563-5 ®
Edition 1.0 2025-02
INTERNATIONAL
STANDARD
Qi Specification version 2.0 –

Part 5: Communications Physical Layer

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.240.99; 35.240.99 ISBN 978-2-8327-0188-1

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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
QI SPECIFICATION VERSION 2.0 –
Part 5: Communications Physical Layer
FOREWORD
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IEC 635-5 has been prepared by technical area 15: Wireless Power Transfer, of IEC
technical committee 100: Audio, video and multimedia systems and equipment. It is an
International Standard.
It is based on Qi Specification version 2.0, Communications Physical Layer and was submitted
as a Fast-Track document.
The text of this International Standard is based on the following documents:
Draft Report on voting
//FDIS //RVD
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Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
The structure and editorial rules used in this publication reflect the practice of the organization
which submitted it.
This document was developed in accordance with ISO/IEC Directives, Part 1 and ISO/IEC
Directives, IEC Supplement available at www.iec.ch/members_experts/refdocs. The main
document types developed by IEC are described in greater detail at www.iec.ch/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
x reconfirmed,
x withdrawn, or
x revised.
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WIRELESS POWER
CONSORTIUM
Qi Specification
Communications Physical Layer
Version 2.0
April 2023
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DISCLAIMER
Theinformationcontainedhereinisbelievedtobeaccurateasofthedateofpublication,
butisprovided“asis”andmaycontainerrors.TheWirelessPowerConsortiummakesno
warranty,expressorimplied,withrespecttothisdocumentanditscontents,includingany
warrantyoftitle,ownership,merchantability,orfitnessforaparticularuseorpurpose.
NeithertheWirelessPowerConsortium,noranymemberoftheWirelessPower
Consortiumwillbeliableforerrorsinthisdocumentorforanydamages,includingindirect
orconsequential,fromuseoforrelianceontheaccuracyofthisdocument.For any further
explanation of the contents of this document, or in case of any perceived inconsistency or ambiguity
of interpretation, contact: [e-mail].
RELEASE HISTORY
Specification Version Release Date Description
v2.0 April 2023 Initial release of the v2.0 Qi Specification.

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Table of Contents
1  General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1 Structure of the Qi Specification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3 Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.4 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.5 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.6 Power Profiles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2  Load Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1 Modulation scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Bit encoding scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.3 Byte encoding scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.4 Data packet structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3  Frequency-shift keying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.1 Modulation scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.2 Bit encoding scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.3 Byte encoding scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.4 Data packet structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3.5 Response Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

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1 General
The Wireless Power Consortium (WPC) is a worldwide organization that aims to develop and
promote global standards for wireless power transfer in various application areas. A first
application area comprises flat-surface devices such as mobile phones and chargers in the
Baseline Power Profile (up to 5 W) and Extended Power Profile (above 5 W).
1.1 Structure of the Qi Specification
General documents
ƒ Introduction
ƒ Glossary, Acronyms, and Symbols
System description documents
ƒ Mechanical, Thermal, and User Interface
ƒ Power Delivery
ƒ Communications Physical Layer
ƒ Communications Protocol
ƒ Foreign Object Detection
ƒ NFC Tag Protection
ƒ Authentication Protocol
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1.2 Scope
The CommunicationsPhysicalLayer (this document) defines the low-level (physical layer and the
data link layer) formats of data bits, data bytes, and data packets. In addition, it provides
requirements and guidelines for load modulation and frequency-shift keying.
1.3 Compliance
All provisions in the QiSpecification are mandatory, unless specifically indicated as recommended,
optional, note, example, or informative. Verbal expression of provisions in this Specification follow
the rules provided in ISO/IEC Directives, Part 2.
Table 1: Verbal forms for expressions of provisions
Provision Verbal form
requirement “shall” or “shall not”
recommendation “should” or “should not”
permission “may” or “may not”
capability “can” or “cannot”
1.4 References
For undated references, the most recently published document applies. The most recent WPC
publications can be downloaded from http://www.wirelesspowerconsortium.com.

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1.5 Conventions
1.5.1 Notation of numbers
ƒ Real numbers use the digits 0 to 9, a decimal point, and optionally an exponential part.
ƒ Integer numbers in decimal notation use the digits 0 to 9.
ƒ Integer numbers in hexadecimal notation use the hexadecimal digits 0 to 9 and A to F, and are
prefixed by "0x" unless explicitly indicated otherwise.
ƒ Single bit
...