ISO 17987-8:2019

INTERNATIONAL ISO
STANDARD 17987-8
First edition
2019-10
Road vehicles — Local Interconnect
Network (LIN) —
Part 8:
Electrical physical layer (EPL)
specification: LIN over DC powerline
(DC-LIN)
Véhicules routiers — Réseau Internet local (LIN) —
Partie 8: Spécification de couche physique électrique (EPL): LIN sur
ligne d'alimentation en courant continu (DC-LIN)
Reference number
©
ISO 2019
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland
ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols, and abbreviated terms . 1
3.1 Terms and definitions . 2
3.2 Symbols and abbreviated terms. 2
4 Electrical physical layer requirements . 5
4.1 General . 5
4.2 Transmitter characteristics . 6
4.2.1 Transmit signal specification . 6
4.2.2 Byte field modulation scheme . 7
4.2.3 Break field modulation scheme .14
4.2.4 Wake-up signal modulation scheme .15
4.3 Timing requirements .18
4.3.1 Bit rate tolerance .18
4.3.2 Bit timing .19
4.3.3 Bit sample timing .19
4.3.4 TXD assert timeout event .19
4.3.5 Delay between transmitted byte field (DC-LIN node A) and received byte
field (DC-LIN node A).19
4.3.6 Delay between transmitted byte field (DC-LIN node A) and received byte
field (DC-LIN node B) . .19
4.4 Receiver characteristics .21
4.5 Electrical parameters .21
4.5.1 General configuration — Coupling to the DC powerline .21
4.5.2 Signal specification .22
4.5.3 Line-out monitoring .23
4.5.4 ESD compliance .28
4.6 Communication in the presence of faults.28
Annex A (informative) DC-LIN EPL peripheral interface design considerations .30
Annex B (normative) DC-LIN EPL conformance test plan .31
Bibliography .56
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso
.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 31,
Data communication.
A list of all parts in the ISO 17987 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2019 – All rights reserved

Introduction
ISO 17987 (all parts) specifies the use cases, communication protocol and physical layer requirements
of an in-vehicle communication network called Local Interconnect Network (LIN).
The LIN protocol as proposed is an automotive-focused low speed UART-based network (Universal
Asynchronous Receiver Transmitter). Some of the key characteristics of the LIN protocol are signal-
based communication, schedule table-based frame transfer, master/slave communication with error
detection, node configuration and diagnostic service transportation.
The LIN protocol is for low cost automotive control applications, for example door module and air
conditioning systems. It serves as a communication infrastructure for low-speed control applications
in vehicles by providing:
— signal-based communication to exchange information between applications in different nodes;
— bit rate support from 1 kbit/s to 20 kbit/s;
— deterministic schedule table-based frame communication;
— network management that wakes up and puts the LIN cluster into sleep mode in a controlled manner;
— status management that provides error handling and error signalling;
— transport layer that allows large amount of data to be transported (such as diagnostic services);
— specification of how to handle diagnostic services;
— electrical physical layer specifications;
— node description language describing properties of slave nodes;
— network description file describing behaviour of communication;
— application programmer's interface.
ISO 17987 (all parts) is based on the open systems interconnection (OSI) basic reference model as
specified in ISO/IEC 7498-1 which structures communication systems into seven layers.
The OSI model structures data communication into seven layers called (top down) application layer
(layer 7), presentation layer, session layer, transport layer, network layer, data link layer and physical
layer (layer 1). A subset of these layers is used in ISO 17987 (all parts).
ISO 17987 (all parts) distinguishes between the services provided by a layer to the layer above it and
the protocol used by the layer to send a message between the peer entities of that layer. The reason for
this distinction is to make the services, especially the application layer services and the transport layer
services, reusable also for other types of networks than LIN. In this way, the protocol is hidden from the
service user and it is possible to change the protocol if special system requirements demand it.
ISO 17987 (all parts) provides all documents and references required to support the implementation of
the requirements related to the following.
— ISO 17987-1: This part provides an overview of the ISO 17987 (all parts) and structure along with
the use case definitions and a common set of resources (definitions, references) for use by all
subsequent parts.
— ISO 17987-2: This part specifies the requirements related to the transport protocol and the network
layer requirements to transport the PDU of a message between LIN nodes.
— ISO 17987-3: This part specifies the requirements for implementations of the LIN protocol on the
logical level of abstraction. Hardware related properties are hidden in the defined constraints.
— ISO 17987-4: This part specifies the requirements for implementations of active hardware
components which are necessary to interconnect the protocol implementation.
— ISO/TR 17987-5: This part specifies the LIN application programmers interface (API) and the
node configuration and identification services. The node configuration and identification services
are specified in the API and define how a slave node is configured and how a slave node uses the
identification service.
— ISO 17987-6: This part specifies tests to check the conformance of the LIN protocol implementation
according to ISO 17987-2 and ISO 17987-3. This comprises tests for the data link layer, the network
layer and the transport layer.
— ISO 17987-7: This part specifies tests to check the conformance of the LIN electrical physical layer
implementation (logical level of abstraction) according to ISO 17987-4.
— ISO 17987-8: This part specifies the requirements for implementations of the DC powerline electrical
physical layer (EPL) for the LIN communications system as well as a conformance test plan for the EPL.
vi © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 17987-8:2019(E)
Road vehicles — Local Interconnect Network (LIN) —
Part 8:
Electrical physical layer (EPL) specification: LIN over DC
powerline (DC-LIN)
1 Scope
This document specifies an additional electrical physical layer (EPL) for the Local Interconnect Network
(LIN) of the ISO 17987 series. It specifies the transmission over DC powerline without affecting the LIN
higher layers, hereafter named DC-LIN.
The DC-LIN EPL uses a high-frequency modulated carrier to propagate UART bytes (byte-oriented)
over the DC powerline.
This document specifies the electrical characteristics, the modulation method of the transmission, and
how to impose the carrier signal on the DC powerlines.
The DC-LIN EPL supports bit rates of 9 615 bit/s, 10 417 bit/s, and 19 230 bit/s.
The DC-LIN EPL is
...