Road vehicles -- Controller area network (CAN)

ISO 11898-2:2016 specifies the high-speed physical media attachment (HS-PMA) of the controller area network (CAN), a serial communication protocol that supports distributed real-time control and multiplexing for use within road vehicles. This includes HS-PMAs without and with low-power mode capability as well as with selective wake-up functionality. The physical media dependant sublayer is not in the scope of this document.

Véhicules routiers -- Gestionnaire de réseau de communication (CAN)

General Information

Status
Published
Publication Date
13-Dec-2016
Current Stage
6060 - International Standard published
Start Date
04-Nov-2016
Completion Date
14-Dec-2016
Ref Project

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INTERNATIONAL ISO
STANDARD 11898-2
Second edition
2016-12-15
Road vehicles — Controller area
network (CAN) —
Part 2:
High-speed medium access unit
Véhicules routiers — Gestionnaire de réseau de communication
(CAN) —
Partie 2: Unité d’accès au support à haute vitesse
Reference number
ISO 11898-2:2016(E)
ISO 2016
---------------------- Page: 1 ----------------------
ISO 11898-2:2016(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form

or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior

written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of

the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2016 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 11898-2:2016(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Symbols and abbreviated terms ........................................................................................................................................................... 2

5 Functional description of the HS-PMA ........................................................................................................................................... 3

5.1 General ........................................................................................................................................................................................................... 3

5.2 HS-PMA test circuit ............................................................................................................................................................................. 3

5.3 Transmitter characteristics .......................................................................................................................................................... 4

5.4 Receiver characteristics .................................................................................................................................................................. 8

5.5 Receiver input resistance ............................................................................................................................................................... 9

5.6 Transmitter and receiver timing behaviour .................................................................................................................. 9

5.7 Maximum ratings of V , V and V ............................................................................................................

CAN_H CAN_L Diff 11

5.8 Maximum leakage currents of CAN_H and CAN_L .................................................................................................12

5.9 Wake-up from low-power mode ...........................................................................................................................................12

5.9.1 Overview ..............................................................................................................................................................................12

5.9.2 Basic wake-up..................................................................................................................................................................13

5.9.3 Wake-up pattern wake-up ....................................................................................................................................13

5.9.4 Selective wake-up ...................................................................... ...................................................................................13

5.10 Bus biasing ...............................................................................................................................................................................................18

5.10.1 Overview ..............................................................................................................................................................................18

5.10.2 Normal biasing ...............................................................................................................................................................18

5.10.3 Automatic voltage biasing .....................................................................................................................................18

6 Conformance ..........................................................................................................................................................................................................20

Annex A (informative) ECU and network design ...................................................................................................................................21

Annex B (informative) PN physical layer modes ...................................................................................................................................29

Bibliography .............................................................................................................................................................................................................................30

© ISO 2016 – All rights reserved iii
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ISO 11898-2:2016(E)
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 on 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 the following URL: www.iso.org/iso/foreword.html.

The committee responsible for this document is ISO/TC 22, Road vehicles, Subcommittee SC 31, Data

communication.

This second edition cancels and replaces the first edition (ISO 11898-2:2003), which has been

technically revised, with the following changes:
— max output current on CANH/CANL has been defined (Table 4);
— optional TXD timeout has been defined (Table 7);
— receiver input resistance range has been changed (Table 10);

— Bit timing parameters for CAN FD for up to 2 Mbps have been defined (Table 13);

— Bit timing parameters for CAN FD for up to 5 Mbps have been defined (Table 14);

— content of ISO 11898-5 and ISO 11898-6 has been integrated to ensure there is one single ISO

Standard for all HS-PMA implementations;
— selective wake-up (formerly ISO 11898-6) CAN FD tolerance has been defined;
— wake-filter timings (formerly in ISO 11898-5) have been changed (Table 20)

— requirements and assumptions about the PMD sublayer have been shifted to Annex A, to clearly

focus on the HS-PMA implementation.
A list of all parts in the ISO 11898 series can be found on the ISO website.
iv © ISO 2016 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 11898-2:2016(E)
Introduction

ISO 11898 was first published as one document in 1993. It covered the CAN data link layer as well as

the high-speed physical layer. In the reviewed and restructured ISO 11898 series, ISO 11898-1 and

ISO 11898-4 defined the CAN protocol and time-triggered CAN (TTCAN) while ISO 11898-2 defines the

high-speed physical layer, and ISO 11898-3 defined the low-speed fault tolerant physical layer.

Figure 1 shows the relation of the Open System Interconnection (OSI) layers and its sublayers to

ISO 11898-1, this document as well as ISO 11898-3.
Key
AUI attachment unit interface
MDI media dependant interface
OSI open system interconnection
Figure 1 — Overview of ISO 11898 specification series

The International Organization for Standardization (ISO) draws attention to the fact that it is claimed

that compliance with this document may involve the use of a patent concerning the selective wake-up

function given in 5.9.4.

ISO takes no position concerning the evidence, validity and scope of this patent right.

The holder of this patent right has assured ISO that he/she is willing to negotiate licenses under

reasonable and non-discriminatory terms and conditions with applicants throughout the world. In

this respect, the statement of the holder of this patent right is registered with ISO. Information may be

obtained from the following:
© ISO 2016 – All rights reserved v
---------------------- Page: 5 ----------------------
ISO 11898-2:2016(E)
Audi AG Elmos Semiconductor AG Renesas Electronics Europe GmbH
August-Horch-Str. Heinrich-Hertz-Str. 1 Arcadiastr. 10
85045 Ingolstadt 44227 Dortmund 40472 Düsseldorf
Germany Germany Germany
BMW Group Freescale Semiconductor Inc. Robert Bosch GmbH
Knorrstr. 147 6501 W. William Canon Drive PO Box 30 02 20
80788 München Austin, Texas 70442 Stuttgart
Germany United States Germany

Continental Teves AG & Co. oHG General Motors Corp. STMicroelectronics Application

Guerickestr. 7 30001 VanDyke, Bldg 2-10 GmbH
60488 Frankfurt am Main Warren, MI 48090-9020 Bahnhofstrasse 18
Germany United States of America 85609 Aschheim Dornach
Germany
DENSO CORP. NXP BV Volkswagen AG
1-1, Showa-cho, Kariya-shi High Tech Campus 60 PO Box 011/1770
Aichi-ken 448-8661 5656 AG Eindhoven 38436 Wolfsburg
Japan The Netherlands Germany

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights other than those identified above. ISO shall not be held responsible for identifying any

or all such patent rights. ISO (www.iso.org/patents) maintains on-line databases of patents relevant

to their standards. Users are encouraged to consult the databases for the most up to date information

concerning patents.
vi © ISO 2016 – All rights reserved
---------------------- Page: 6 ----------------------
INTERNATIONAL STANDARD ISO 11898-2:2016(E)
Road vehicles — Controller area network (CAN) —
Part 2:
High-speed medium access unit
1 Scope

This document specifies the high-speed physical media attachment (HS-PMA) of the controller area

network (CAN), a serial communication protocol that supports distributed real-time control and

multiplexing for use within road vehicles. This includes HS-PMAs without and with low-power mode

capability as well as with selective wake-up functionality. The physical media dependant sublayer is

not in the scope of this document.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 11898-1:2015, Road vehicles — Controller area network (CAN) — Part 1: Data link layer and physical

signalling

ISO 16845-2, Road vehicles — Controller area network (CAN) conformance test plan — Part 2: High-speed

medium access unit with selective wake-up functionality
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 11898-1 and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
NOTE See Figure A.1 for a visualization of the definitions.
3.1
attachment unit interface
AUI

interface between the PCS that is specified in ISO 11898-1 and the PMA that is specified in this document

3.2
ground
GND
electrical signal ground
3.3
legacy implementation

HS-PMA implementation that has been released prior to the publication of this document

© ISO 2016 – All rights reserved 1
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ISO 11898-2:2016(E)
3.4
low-power mode

mode in which the transceiver is not capable of transmitting or receiving messages, except for the

purposes of determining if a WUP or WUF is being received
3.5
medium attachment unit
MAU

unit that comprises the physical media attachment and the media dependent interface

3.6
media dependent interface
MDI

interface that ensures proper signal transfer between the media and the physical media attachment

3.7
normal-power mode

mode in which the transceiver is fully capable of transmitting and receiving messages

3.8
physical coding sublayer
PCS
sublayer that performs bit encoding/decoding and synchronization
3.9
physical media attachment
PMA
sublayer that converts physical signals into logical signals and vice versa
3.10
transceiver
implementation that comprises one or more physical media attachments
4 Symbols and abbreviated terms

For the purposes of this document, the symbols and abbreviated terms given in ISO 11898-1 and the

following apply. Some of these abbreviations are also defined in ISO 11898-1. If the definition of the

term in this document is different from the definition in ISO 11898-1, this definition applies.

AUI attachment unit interface
DLC data length code
EMC electromagnetic compatibility
ESD electro static discharge
GND ground
HS-PMA high-speed PMA
MAU medium attachment unit
MDI media dependent interface
PCS physical coding sublayer
PMA physical media attachment
2 © ISO 2016 – All rights reserved
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ISO 11898-2:2016(E)
PMD physical media dependent
WUF wake-up frame
WUP wake-up pattern
5 Functional description of the HS-PMA
5.1 General

The HS-PMA comprises one transmitter and one receiving entity. It shall be able to bias the connected

physical media, an electric two-wire cable, relative to a common ground. The transmitter entity shall

drive a differential voltage between the CAN_H and CAN_L signals to signal a logical 0 (dominant)

or shall not drive a differential voltage to signal a logical 1 (recessive) to be received by other nodes

connected to the very same media. These two signals are the interface to the physical media dependent

sublayer.

The HS-PMA shall provide an AUI to the physical coding sublayer as specified in ISO 11898-1. It

comprises the TXD and RXD signals as well as the GND signal. The TXD signal receives from the physical

coding sublayer the bit-stream to be transmitted on the MDI. The RXD signal transmits to the physical

coding sublayer the bit-stream received from the MDI.

Implementations that comprise one or more HS-PMAs shall at least support the normal-power mode of

operation. Optionally, a low-power mode may be implemented.

Some of the items specified in the following depend on the operation mode of the (part of the)

implementation, in which the HS-PMA is included.

Table 1 shows the possible combinations of HS-PMA operating modes and expected behaviour.

Table 1 — HS-PMA operating modes and expected behaviour
Operating mode Bus biasing behaviour Transmitter behaviour
Normal Bus biasing active Dominant or recessive
Low-power Bus biasing active or inactive Recessive
Depends on input conditions as described in this document.

All parameters given in this subclause shall be fulfilled throughout the operating temperature range

and supply voltage range (if not explicitly specified for unpowered) as specified individually for every

HS-PMA implementation.
5.2 HS-PMA test circuit

The outputs of the HS-PMA implementation to the CAN signals are called CAN_H and CAN_L, TXD is

the transmit data input and RXD is the receive data output. Figure 2 shows the external circuit that

defines the measurement conditions for all required voltage and current parameters. R represents

the effective resistive load (bus load) for an HS-PMA implementation, when used in a network, and C

represents an optional split-termination capacitor. The values of R and C vary for different parameters

L 1

that the HS-PMA implementation needs to meet and are given as condition in Tables 2 to 20.

© ISO 2016 – All rights reserved 3
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ISO 11898-2:2016(E)
Key
V differential voltage between CAN_H and CAN_L wires
Diff
V single ended voltage on CAN_H wire
CAN_H
V single ended voltage on CAN_L wire
CAN_L
C capacitive load on RXD
RXD
Figure 2 — HS-PMA test circuit
5.3 Transmitter characteristics

This subclause specifies the transmitter characteristics of a single HS-PMA implementation under the

conditions as depicted in Figure 2; so no other HS-PMA implementations are connected to the media.

The behaviour of an HS-PMA implementation connected to other HS-PMAs is outside the scope of this

subclause. Refer to A.2 for consideration when multiple HS-PMAs are connected to the same media. The

voltages and currents that are required on the CAN_L and CAN_H signals are specified in Tables 2 to 6.

Table 2 specifies the output characteristics during dominant state.
Figure 3 illustrates the voltage range for the dominant state.
4 © ISO 2016 – All rights reserved
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ISO 11898-2:2016(E)
Table 2 — HS-PMA dominant output characteristics
Value
Parameter Notation Condition
Min Nom Max
V V V
Single ended voltage on CAN_H V +2,75 +3,5 +4,5 R = 50 Ω …65 Ω
CAN_H L
Single ended voltage on CAN_L V +0,5 +1,5 +2,25 R = 50 Ω …65 Ω
CAN_L L
Differential voltage on normal bus load V +1,5 +2,0 +3,0 R = 50 Ω …65 Ω
Diff L
Differential voltage on effective resistance Not
V +1,5 +5,0 R = 2 240 Ω
Diff L
during arbitration defined
Optional:
V +1,4 +2,0 +3,3 R = 45 Ω …70 Ω
Diff L
Differential voltage on extended bus load
range

2 240 Ω is emulating a situation with up to 32 nodes sending dominant simultaneously. In such case, the effective load

resistance for a single node decreases (a node does drive only a part of the nominal bus load). Assuming a MAX R of 70 Ω,

this scenario covers a 32 nodes network. (2 240 Ω/70 Ω per node = 32 nodes.)

All requirements in this table apply concurrently. Therefore, not all combinations of V and V are compliant with

CAN_H CAN_L
the defined differential voltage (see Figure 3).
Measurement setup according to Figure 2 (only one HS-PMA present):
R , see “Condition” column above
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD
Key
V differential voltage between CAN_H and CAN_L wires
Diff
V single ended voltage on CAN_H wire
CAN_H
V single ended voltage on CAN_L wire
CAN_L

Figure 3 — Voltage range of V during dominant state of CAN node, when V varies from

CAN_H CAN_L
minimum to maximum voltage level (50 Ω … 65 Ω bus load condition)
© ISO 2016 – All rights reserved 5
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ISO 11898-2:2016(E)

In order to achieve a level of RF emission that is acceptably low, the transmitter shall meet the driver

signal symmetry as required in Table 3.
Table 3 — HS-PMA driver symmetry
Value
Parameter Notation
Min Nom Max
Driver symmetry v +0,9 +1,0 +1,1
sym
v = (V + V )/V , with V being the supply voltage of the transmitter.
sym CAN_H CAN_L CC CC

v shall be observed during dominant and recessive state and also during the transition from dominant to

sym

recessive and vice versa, while TXD is stimulated by a square wave signal with a frequency that corresponds

to the highest bit rate for which the HS-PMA implementation is intended, however, at most 1 MHz (2 Mbit/s)

(HS-PMA in normal mode).
Measurement setup according to Figure 2:
R = 60 Ω (tolerance ≤ ±1 %)
C = 4,7 nF (tolerance ≤ ±5 %)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

The maximum output current of the transmitter shall be limited according to Table 4.

Table 4 — Maximum HS-PMA driver output current
Value
Parameter Notation Condition
Min Max
mA mA
Absolute current on CAN_H I not defined 115 −3 V ≤ V ≤ +18 V
CAN_H CAN_H
Absolute current on CAN_L I not defined 115 −3 V ≤ V ≤ +18 V
CAN_L CAN_L

Measurement setup according to Figure 2 with either V or V enforced to voltage levels as mentioned in the

CAN_H CAN_L

conditions by connection to an external voltage source, while the HS-PMA is driving the output dominant. The absolute

maximum value does not care about the direction in which the current flows.
R > 10 Ω (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

NOTE It is expected that the implementation does not stop driving its output dominant when the differential voltage

between CAN_H and CAN_L is outside the limits given in the Condition column. The minimum output current is implicitly

defined in Table 2 and thus can be expected to be above 30 mA.

Table 5 specifies the recessive output characteristics when bus biasing is active.

6 © ISO 2016 – All rights reserved
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ISO 11898-2:2016(E)
Table 5 — HS-PMA recessive output characteristics, bus biasing active
Value
Parameter Notation
Min Nom Max
V V V
Single ended output voltage on CAN_H V +2,0 +2,5 +3,0
CAN_H
Single ended output voltage on CAN_L V +2,0 +2,5 +3,0
CAN_L
Differential output voltage V −0,5 0 +0,05
Diff

All requirements in this table apply concurrently. Therefore, not all combinations of V and V are compliant with

CAN_H CAN_L
the defined differential output voltage.
Measurement setup according to Figure 2:
R > 10 Ω (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

Table 6 specifies the recessive output characteristics when bus biasing is inactive.

Table 6 — HS-PMA recessive output characteristics, bus biasing inactive
Value
Parameter Notation
Min Nom Max
V V V
Single ended output voltage on CAN_H V −0,1 0 +0,1
CAN_H
Single ended output voltage on CAN_L V −0,1 0 +0,1
CAN_L
Differential output voltage V −0,2 0 +0,2
Diff
See 5.10 to determine when bias shall be inactive.
Measurement setup according to Figure 2:
R > 10 Ω (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

The implementation of an HS-PMA may limit the duration of dominant transmission in order not to

prevent other CAN nodes from communication when the TXD input is permanently asserted. The HS-

PMA implementation should implement a timeout within the limits specified in Table 7.

Table 7 — Optional HS-PMA transmit dominant timeout
Value
Parameter Notation
Min Max
ms ms
Transmit dominant timeout t 0,8 10,0
dom
A minimum value of 0,3 ms is accepted for legacy implementations.

NOTE There is a relation between the t minimum value and the minimum bit rate. A t minimum

dom dom

value of 0,8 ms accommodates 17 consecutive dominant bits at bit rates greater than or equal to 21,6 kbit/s

and 36 consecutive dominant bits at bit rates greater than or equal to 45,8 kbit/s. The value 17 reflects PMA

implementation attempts to send a dominant bit and every time sees a recessive level at the receive data input.

The value 36 reflects six consecutive error frames when there is a bit error in the last bit of the first five attempts.

© ISO 2016 – All rights reserved 7
---------------------- Page: 13 ----------------------
ISO 11898-2:2016(E)
5.4 Receiver characteristics

The receiver uses the transmitter output signals CAN_H and CAN_L as differential input. Figure 2 shows

the definition of the voltages at the connections of the HS-PMA’s implementation.

When the HS-PMA implementation is in its low-power mode and bus biasing is active, then the recessive

and dominant state differential input voltage ranges according to Table 8 apply.
Table 8 — HS-PMA static receiver input characteristics, bus biasing active
Value
Parameter Notation Condition
Min Max
V V
Recessive state differential input voltage −12,0 V ≤ V ≤ +12,0 V
CAN_L
V −3,0 +0,5
Diff
range
−12,0 V ≤ V ≤ +12,0 V
CAN_H
Dominant state differential input voltage −12,0 V ≤ V ≤ +12,0 V
CAN_L
V +0,9 +8,0
Diff
range
12,0 V ≤ V ≤ +12,0 V
CAN_H
Measurement setup according Figure 2:
R > 10 Ω (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

NOTE A negative differential voltage may temporarily occur when the HS-PMA is connected to a media in which common

mode chokes and/or unterminated stubs are present. The maximum positive differential voltage may temporarily occur

when the HS-PMA is connected to a media while more than one HS-PMA is sending dominant and concurrently a ground

shift between the sending HS-PMAs is present.

When the HS-PMA implementation is in its low-power mode and bus biasing is inactive, then the

recessive and dominant state differential input voltage ranges according to Table 9 apply.

Table 9 — HS-PMA static receiver input characteristics, bus biasing inactive
Value
Parameter Notation Condition
Min Max
V V
Recessive state differential input −12,0 V ≤ V ≤ +12,0 V
CAN_L
V −3,0 +0,4
Diff
voltage range
−12,0 V ≤ V ≤ +12,0 V
CAN_H
Dominant state differential input −12,0 V ≤ V ≤ +12,0 V
CAN_L
V +1,15 +8,0
Diff
voltage range
−12,0 V ≤ V ≤ +12,0 V
CAN_H
Measurement setup according Figure 2:
R >10 Ω (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

NOTE A negative differential voltage may temporarily occur when the HS-PMA is connected to a media in which common

mode chokes and/or unterminated stubs are present. The maximum positive differential voltage may temporarily occur

when the HS-PMA is connected to a media while more than one HS-PMA is sending dominant and concurrently a ground

shift between the sending HS-PMAs is present.
8 © ISO 2016 – All rights reserved
---------------------- Page: 14 ----------------------
ISO 11898-2:2016(E)
5.5 Receiver input resistance

The implementation of an HS-PMA shall have an input resistance according to Table 10. Furthermore,

the internal resistance shall meet the requirement given in Table 11. Figure 4 shows an equivalent

circuit diagram.
Figure 4 — Illustration of HS-PMA internal differential input resistance
Table 10 — HS-PMA receiver input resistance
Value
Parameter Notation Condition
Min Max
kΩ kΩ
Differential internal resistance R 12 100
Diff
−2 V ≤ V ,
CAN_L
R ,
CAN_H
Single ended internal resistance 6 50
V ≤ +7 V
CAN_H
CAN_L
R = R + R
Diff CAN_H CAN_L
Table 11 — HS-PMA receiver input resistance matching
Value
Parameter Notation Condition
Min Max
V , V :
CAN_L CAN_H
Matching of internal resistance m −0,03 +0,03
+5 V
The matching shall be calculated as m = 2 × (R − R )/(R + R ).
R CAN_H CAN_L CAN_H CAN_L
5.6 Transmitter and receiver timing behaviour

The timing is defined under consideration of the test circuit that is shown in Figure 2. The parameters

are given in Tables 12, 13 and 14 and shall be measured at the RXD output and TXD input of the HS-PMA

implementation as well as on the differential voltage between CAN_H and CAN_L.
Figure 5 shows how to measure the timing in the signal traces.
© ISO 2016 – All rights reserved 9
---------------------- Page: 15 ----------------------
ISO 11898-2:2016(E)
Key

t = 1 000 ns if the implementation of the HS-PMA supports bit rates of up to 1 Mbit/s

Bit(TXD)

t = 500 ns if the implementation of the HS-PMA supports bit rates of up to 2 Mbit/s

Bit(TXD)

t = 200 ns if the implementation of the HS-PMA supports bit rates of up to 5 Mbit/s

Bit(TXD)
Figure 5 — HS-PMA i
...

DRAFT INTERNATIONAL STANDARD
ISO/DIS 11898-2
ISO/TC 22/SC 31 Secretariat: DIN
Voting begins on: Voting terminates on:
2015-12-17 2016-03-16
Road vehicles — Controller area network (CAN) —
Part 2:
High-speed medium access unit
Véhicules routiers — Gestionnaire de réseau de communication (CAN) —
Partie 2: Unité d’accès au support à haute vitesse
ICS: 43.040.15
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 11898-2:2015(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. ISO 2015
---------------------- Page: 1 ----------------------
ISO/DIS 11898-2:2015(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form

or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior

written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of

the requester.
ISO copyright office
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copyright@iso.org
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ii © ISO 2015 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/DIS 11898-2:2015(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Symbols and abbreviated terms ........................................................................................................................................................... 2

5 Functional description of the HS-PMA ........................................................................................................................................... 2

5.1 General ........................................................................................................................................................................................................... 2

5.2 HS-PMA test circuit ............................................................................................................................................................................. 3

5.3 Transmitter characteristics .......................................................................................................................................................... 3

5.4 Receiver characteristics .................................................................................................................................................................. 6

5.5 Receiver input resistance ............................................................................................................................................................... 7

5.6 Transmitter and receiver timing behaviour .................................................................................................................. 8

5.7 Maximum ratings of V , V and V ............................................................................................................

CAN_H CAN_L Diff 10

5.8 Maximum leakage currents of CAN_H and CAN_L .................................................................................................11

5.9 Wake-up from low-power mode ...........................................................................................................................................11

5.9.1 Overview ..............................................................................................................................................................................11

5.9.2 Basic wake-up..................................................................................................................................................................11

5.9.3 Wake-up pattern wake-up ....................................................................................................................................12

5.9.4 Selective wake-up ...................................................................... ...................................................................................12

5.10 Bus biasing ...............................................................................................................................................................................................17

5.10.1 Overview ..............................................................................................................................................................................17

5.10.2 Normal biasing ...............................................................................................................................................................17

5.10.3 Automatic voltage biasing .....................................................................................................................................17

6 Conformance ..........................................................................................................................................................................................................20

Annex A (informative) ECU and network design ...................................................................................................................................21

© ISO 2015 – All rights reserved iii
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ISO/DIS 11898-2:2015(E)
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.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. Draft International

Standards adopted by the technical committees are circulated to the member bodies for voting.

Publication as an International Standard requires approval by at least 75 % of the member bodies

casting a vote.

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.

ISO 11898-2 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 31, Data

communication.

ISO 11898 consists of the following parts, under the general title Road vehicles — Controller area

network (CAN):
— Part 1: Data link layer and physical signalling
— Part 2: High-speed medium access unit
— Part 3: Low-speed fault tolerant physical medium attachment
— Part 4: Time-triggered communication
iv © ISO 2015 – All rights reserved
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ISO/DIS 11898-2:2015(E)
Introduction

ISO 11898 was first published as one document in 1993. It covered the CAN data link layer as well as

the high-speed physical layer. In the reviewed and restructured ISO 11898- series parts 1 and 4 defined

the CAN protocol and time-triggered CAN (TTCAN) while the parts 2, 5 and 6 defined the high-speed

physical layer, and part 3 defined the low-speed fault tolerant physical layer.

ISO 11898-2:2003, ISO 11898-5:2007 and ISO 11898-6:2013 have been withdrawn and replaced by this

version of ISO 11898-2.

Figure 1 shows the relation of the OSI (Open System Interconnection) layers and its sub-layers to the

ISO 11898 part 1 and part 2 as well as part 3.
Key
AUI attachment unit interface
MDI media dependant interface
OSI open system interconnection
Figure 1 — Overview of ISO 11898 specification series

The International Organization for Standardization (ISO) [and/or] International Electro-technical

Commission (IEC) draws attention to the fact that it is claimed that compliance with this document may

involve the use of a patent concerning the selective wake-up function given in 5.9.4.

ISO [and/or] IEC take[s] no position concerning the evidence, validity and scope of this patent right.

The holder of this patent right has assured the ISO [and/or] IEC that he/she is willing to negotiate

licenses under reasonable and non-discriminatory terms and conditions with applicants throughout

© ISO 2015 – All rights reserved v
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ISO/DIS 11898-2:2015(E)

the world. In this respect, the statement of the holder of this patent right is registered with ISO [and/or]

IEC. Information may be obtained from:
Audi AG Elmos Semiconductor AG Renesas Electronics Europe GmbH
August-Horch-Str. Heinrich-Hertz-Str. 1 Arcadiastr. 10
85045 Ingolstadt 44227 Dortmund 40472 Düsseldorf
Germany Germany Germany
BMW Group Freescale Semiconductor Inc. Robert Bosch GmbH
Knorrstr. 147 Schatzbogen 7 PO Box 30 02 20
80788 München 81829 München 70442 Stuttgart
Germany Germany Germany

Continental Teves AG & Co. oHG General Motors Corp. STMicroelectronics Application

Guerickestr. 7 30001 VanDyke, Bldg 2-10 GmbH
60488 Frankfurt am Main Warren, MI 48090-9020 Bahnhofstrasse 18
Germany United States of America 85609 Aschheim Dornach
Germany
Denso Japan Corp. NXP BV Volkswagen AG
1-1, Showa-cho, Kariya-shi High Tech Campus 60 PO Box 011/1770
Aichi-ken 448-8661 5656 AG Eindhoven 38436 Wolfsburg
Japan The Netherlands Germany

Attention is drawn to the possibility that some of the elements of this document may be the subject

of patent rights other than those identified above. ISO [and/or] IEC shall not be held responsible for

identifying any or all such patent rights. ISO (www.iso.org/patents) and IEC (http://patents.iec.ch)

maintain on-line databases of patents relevant to their standards. Users are encouraged to consult the

databases for the most up to date information concerning patents.
vi © ISO 2015 – All rights reserved
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DRAFT INTERNATIONAL STANDARD ISO/DIS 11898-2:2015(E)
Road vehicles — Controller area network (CAN) —
Part 2:
High-speed medium access unit
1 Scope

This part of ISO 11898 specifies the high-speed physical media attachment (HS-PMA) of the controller

area network (CAN) a serial communication protocol that supports distributed real-time control

and multiplexing for use within road vehicles. This includes HS-PMAs without and with low-power

capability as well as with selective wake-up functionality. The physical media dependant sub-layer is

not in the scope of this part.
2 Normative references

The following documents, in whole or in part, are normatively referenced in this part and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

ISO/IEC 7498-1:1994, Information technology — Open Systems Interconnection — Basic Reference Model:

The Basic Model — Part 1

ISO 11898-1:2015, Road vehicles — Controller area network (CAN) — Part 1: Data link layer and

physical signalling

ISO 16845-2:2014, Road vehicles — Controller area network (CAN) conformance test plan — Part 2: High-

speed medium access unit with selective wake-up functionality
3 Terms and definitions

For the purpose of this document, the terms and definitions given in ISO 11898-1 and the following

apply. See figure A.1 in Annex A for a visualization of the definitions.
3.1
attachment unit interface (AUI)

The attachment unit interface is the interface between the PCS that is specified in part 1 of ISO 11898

and the PMA that is specified in this of ISO 11898.
3.2
ground (GND)
electrical signal ground
3.3
medium attachment unit (MAU)

unit that comprises the physical media attachment and the media dependent interface

3.4
media dependent interface (MDI)

interface that ensures proper signal transfer between the media and the physical media attachment

3.5
physical coding sublayer (PCS)
sub-layer that performing bit encoding/decoding and synchronization
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ISO/DIS 11898-2:2015(E)
3.6
physical media attachment (PMA)
sub-layer that converts physical signals into logical signals and vice versa
3.7
transceiver
implementation that comprises one or more physical media attachments
4 Symbols and abbreviated terms

For the purpose of this part, the symbols and abbreviated terms given in ISO 11898-1 and the following

apply. Some of these abbreviations are also defined in ISO 11898-1. If the definition of the term here is

different from the definition in ISO 11898-1, this definition applies.
AUI attachment unit interface
EMC electro-magnetic compatibility
ESD electro static discharge
GND ground
HS-PMA high-speed PMA
MAU medium attachment unit
MDI media dependent interface
PCS Physical coding sub-layer
PMA physical media attachment
PMD physical media dependent
WUF wake-up frame
WUP wake-up pattern
5 Functional description of the HS-PMA
5.1 General

The HS-PMA comprises one transmitter and one receiving entity. It shall be able to bias the connected

physical media – an electric two-wire cable – relative to a common ground. The transmitter entity

shall drive a differential voltage between the CAN_H and CAN_L signals to signal a logical 0 (dominant)

respectively a logical 1 (recessive) to be received by other nodes connected to the very same media.

These two-signals are the interface to the physical media dependent sub-layer.

The HS-PMA shall provide an AUI to the physical coding sub-layer as specified in ISO 11898-1. It

comprises the TXD and RXD signals as well as the GND signal. The TXD signal receives from the physical

coding sub-layer the bit-stream to be transmitted on the MDI. The RXD signal transmits to the physical

coding sub-layer the bit-stream received from the MDI.

Implementations that comprise one or more HS-PMAs shall at least support the “normal” mode of

operation. Optionally, a “low-power mode” may be implemented.

Some of the items specified in the following depend on the operation mode of the (part of the)

implementation, in which the HS-PMA is included.

Table 1 shows the possible combinations of HS-PMA operational modes and expected behaviour.

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ISO/DIS 11898-2:2015(E)
Table 1 — HS-PMA operating modes and expected behaviour
Operating mode Bus biasing behaviour Transmitter behaviour
Normal Bus biasing active Dominant or recessive
Low-power Bus biasing active or inactive Recessive
Depends on input conditions as described in this document

All parameters given in this clause of this part shall be fulfilled throughout the operating temperature

range and supply voltage range (if not explicitly specified for unpowered) as specified individually for

every HS-PMA implementation.
5.2 HS-PMA test circuit

The outputs of the HS-PMA implementation to the CAN signals are called CAN_H and CAN_L, TXD is the

transmit data input and RXD the receive data output. Figure 2 shows the external circuit that defines the

measurement conditions for all required voltage and current parameters. R represents the effective

resistive load (bus load) for a HS-PMA implementation, when used in a network and C represents an

optional split-termination capacitor. The values of R and C vary for different parameters that the PMA

L 1
implementation needs to meet and are given as condition in the following tables.
Key
V : Differential voltage between CAN_H and CAN_L wires
Diff
V : Single ended voltage on CAN_H wire
CAN_H
V : Single ended voltage on CAN_L wire
CAN_L
C : Capacitive load on RXD
RXD
Figure 2 — HS-PMA test circuit
5.3 Transmitter characteristics

This section specifies the transmitter characteristics of a single HS-PMA implementation under the

conditions as depicted in Figure 2; so no other HS-PMA implementations connected to the media. The

behaviour of a HS-PMA implementation connected to other HS-PMAs is out of scope in this sub-section.

Refer to section A.2 for consideration when multiple HS-PMAs are connected to the same media. The

voltages and currents that are required on the CAN_L and CAN_H signals are specified in Table 2 to

Table 6. Table 2 specifies the output characteristics during dominant state.
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ISO/DIS 11898-2:2015(E)
Figure 3 illustrates the voltage range for the dominant state.
Table 2 — HS-PMA dominant output characteristics
Parameter Notation Value Condition
Min Nom Max
V V V
Single ended voltage on CAN_H V +2,75 +3,5 +4,5 R = 50 … 65
CAN_H L
Single ended voltage on CAN_L V +0,5 +1,5 +2,25 R = 50 … 65
CAN_L L
Differential voltage on normal bus load V +1,5 +2,0 +3,0 R = 50 … 65
Diff L
Differential voltage on effective resistance V +1,5 Not +5,0 R = 2240
Diff L
during arbitration defined
Optional: V +1,4 +2,0 +3,3 R = 45 … 70
Diff L
Differential voltage on extended bus load
range

All requirements in this table apply concurrently. Therefore, not all combinations of V and V are

CAN_H CAN_L
compliant with the defined differential voltage (see Figure 3).
Measurement setup according to Figure 2 (only one HS-PMA present)
R : see “Condition” - column above
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD
Key
V : differential voltage between CAN_H and CAN_L wires
Diff
V : single ended voltage on CAN_H wire
CAN_H
V : single ended voltage on CAN_L wire
CAN_L
Figure 3 — Voltage range of V during dominant state of CAN node, when V varies
CAN_H CAN_L
from minimum to maximum voltage level (50 Ω…65 Ω bus load condition)
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ISO/DIS 11898-2:2015(E)

In order to achieve a level of RF emission that is acceptably low, the transmitter shall meet the driver

signal symmetry as required by Table 3.
Table 3 — HS-PMA driver symmetry
Parameter Notation Value
Min Nom Max
Driver symmetry v +0,9 +1,0 +1,1
SYM
V = (V + V ) / V , with V being the supply voltage of the transmitter.
SYM CAN_H CAN_L CC CC

V shall be observed during dominant and recessive state and also during the transition from dominant to

SYM

recessive and vice versa, while TXD is stimulated by a square wave signal with a frequency that corresponds

to the highest bit rate for which the HS-PMA implementation is intended, however, at most 1 MHz (2 Mbit/s)

(HS-PMA in normal mode).
Measurement setup according to Figure 2
R = 60 (tolerance ≤ ±1 %)
C = 4,7 nF (tolerance ≤ ±5 %)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

The maximum output current of the transmitter shall be limited according to Table 4.

Table 4 — Maximum HS-PMA driver output current
Parameter Notation Value Condition
Min Max
mA mA
Absolute current on CAN_H I not defined 115 -3 V ≤ V ≤ +18 V
CAN_H CAN_H
Absolute current on CAN_L I not defined 115 -3 V ≤ V ≤ +18 V
CAN_L CAN_L

Measurement setup according to Figure 2 with either V or V enforced to voltage levels as mentioned

CAN_H CAN_L

in the conditions by connection to an external voltage source, while the HS-PMA is driving the output domi-

nant. The absolute maximum value does not care about the direction in that the current flows.

R > 10 (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

NOTE It is expected that the implementation does not stop driving its output dominant when the voltages on

CAN_H and CAN_L are outside the limits mentioned in Table 8.

Table 5 specifies the recessive output characteristics, when bus biasing is active.

Table 5 — HS-PMA recessive output characteristics, bus biasing active
Parameter Notation Value
Min Nom Max
V V V
Single ended output voltage on CAN_H V +2,0 +2,5 +3,0
CAN_H
Single ended output voltage on CAN_L V +2,0 +2,5 +3,0
CAN_L
Differential output voltage V -0,5 0 +0,05
Diff
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ISO/DIS 11898-2:2015(E)
Table 5 (continued)
Parameter Notation Value
Min Nom Max
V V V

All requirements in this table apply concurrently. Therefore, not all combinations of V and V are

CAN_H CAN_L
compliant with the defined differential output voltage.
Measurement setup according to Figure 2
R > 10 (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

Table 6 specifies the recessive output characteristics, when bus biasing is inactive.

Table 6 — HS-PMA recessive output characteristics, bus biasing inactive
Parameter Notation Value
Min Nom Max
V V V
Single ended output voltage on CAN_H V -0,1 0 +0,1
CAN_H
Single ended output voltage on CAN_L V -0,1 0 +0,1
CAN_L
Differential output voltage V -0,2 0 +0,2
Diff
See 5.10, Bus biasing, to determine when bias shall be inactive.
Measurement setup according to Figure 2
R > 10 (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

The implementation of a HS-PMA may limit the duration of dominant transmission in order not to

prevent other CAN nodes from communication when the TXD input is permanently asserted. The HS-

PMA implementation should implement a timeout within the limits specified in Table 7.

Table 7 — Optional HS-PMA transmit dominant timeout
Parameter Notation Value
Min Max
ms ms
Transmit dominant timeout, long t 0,8 10,0
dom
Transmit dominant timeout, short t 0,3 5,0
dom

NOTE There is a relation between the t minimum value and the minimum bit rate. A t minimum

dom dom

value of 0,8 ms accommodates 17 consecutive dominant bits at bit rates greater than or equal to 21,6 kbit/s

and 36 consecutive dominant bits at bit rates greater than or equal to 45,8 kbit/s. The value 17 reflects PMA

implementation attempts to send a dominant bit and every time sees a recessive level at the receive data input.

The value 36 reflects six consecutive error frames when there is a bit error in the last bit of the first five attempts.

5.4 Receiver characteristics

The receiver uses the transmitter output signals CAN_H and CAN_L as differential input. Figure 2 shows

the definition of the voltages at the connections of the HS-PMA’s implementation.

When the HS-PMA implementation is in its low-power mode and bus biasing is active, then the recessive

and dominant state differential input voltage ranges according to Table 8 apply.
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ISO/DIS 11898-2:2015(E)
Table 8 — HS-PMA static receiver input characteristics, bus biasing active
Parameter Notation Value Condition
Min Max
V V
Recessive state differential input voltage V -3,0 +0,5 -12,0 V ≤ V ≤ +12,0 V
Diff CAN_L
range -12,0 V ≤ V ≤ +12,0 V
CAN_H
Dominant state differential input voltage V +0,9 +8,0 -12,0 V ≤ V ≤ +12,0 V
Diff CAN_L
range -12,0 V ≤ V ≤ +12,0 V
CAN_H
Measurement setup according Figure 2.
V , V according to Table 9.
CAN_L CAN_H
R > 10 (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

Note: A negative differential voltage may temporarily occur when the HS-PMA is connected to a media in that

common mode chokes and/or unterminated stubs are present. The maximum positive differential voltage may

temporarily occur when the HS-PMA is connected to a media while more than one HS-PMA is sending dominant

and concurrently a ground shift between the sending HS-PMAs is present.

When the HS-PMA implementation is in its low-power mode and bus biasing is inactive, then the

recessive e and dominant state differential input voltage ranges according to Table 9 apply.

Table 9 — HS-PMA static receiver input characteristics, bus biasing inactive
Parameter Notation Value Condition
Min Max
V V
Recessive state differential input V -3,0 +0,4 -12,0 V ≤ V ≤ +12,0 V
Diff CAN_L
voltage range -12,0 V ≤ V ≤ +12,0 V
CAN_H
Dominant state differential input V +1,15 +8,0 -12,0 V ≤ V ≤ +12,0 V
Diff CAN_L
voltage range -12,0 V ≤ V ≤ +12,0 V
CAN_H
Measurement setup according Figure 2
R >10 (not present)
C = 0 pF (not present)
C = 0 pF (not present)
C = 0 pF (not present)
RXD

Note: A negative differential voltage may temporarily occur when the HS-PMA is connected to a media in that

common mode chokes and/or unterminated stubs are present. The maximum positive differential voltage may

temporarily occur when the HS-PMA is connected to a media while more than one HS-PMA is sending dominant

and concurrently a ground shift between the sending HS-PMAs is present.
5.5 Receiver input resistance

The implementation of a HS-PMA shall have an input resistance according to Table 10. Furthermore

the internal resistance shall meet the requirement given in Table 11. Figure 4 shows an equivalent

circuit diagram:
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ISO/DIS 11898-2:2015(E)
Figure 4 — Illustration of HS-PMA internal differential input resistance
Table 10 — HS-PMA receiver input resistance
Parameter Notation Value
Min Max
k k
Differential internal resistance R 12 100
Diff
Single ended internal resistance R , 6 50
CAN_H
CAN_L
R = R + R
Diff CAN_H CAN_L
Table 11 — HS-PMA receiver input resistance matching
Parameter Notation Value
Min Max
Matching of internal resistance m -0,03 +0,03
The matching shall be calculated as m = 2 x (R - R ) / (R +
R CAN_H CAN_L CAN_H
R )
CAN_L
5.6 Transmitter and receiver timing behaviour

The timing is defined under consideration of the test circuit that is shown in Figure 2. The parameters

are given in Table 12, Table 13 and Table 14 shall be measured at the RXD output and TXD input of the

HS-PMA implementation as well as on the differential voltage between CAN_H and CAN_L.

Figure 5 shows how to measure the timing in the signal traces.
8 © ISO 2015 – All rights reserved
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ISO/DIS 11898-2:2015(E)
Key

t = 1 000 ns if the implementation of the HSPMA supports bit rates of up to 1 Mbit/s

Bit(TXD)

t = 500 ns if the implementation of the HS PMA supports bit rates of up to 2 Mbit/s

Bit(TXD)

t = 200 ns if the implementation of the HS PMA supports bit rates of up to 5 Mbit/s

Bit(TXD)
Figure 5 — HS-PMA implementation timing diagram
Table 12 — HS-PMA implementation loop delay requirement
Parameter Notation Value
Min Max
ns ns
Loop delay t not defined 255
Loop

Time span from signal edge on TXD input to next signal edge with same polarity on RXD output, the

maximum of delay of both signal edges is to be considered.
Measurement setup according to Figure 2:
R = 60 Ω (tolerance ≤ ±1 %)
C = 0 pF (not present)
C = 100 pF (tolerance ≤ ±1 %)
C = 15 pF (tolerance ≤ ±1 %)
RXD
Measurement according to Figure 5:

The input signal on TXD shall have rise- and fall times (10 % / 90 %) of less than 10 ns.

Note: Limits for t and t are not defined for intended use with bit rates up to 1 Mbit/s.

Bit(Bus) Bit(RXD)
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ISO/DIS 11898-2:2015(E)
Table 13 — Optional HS-PMA implementation data signal timing requirements
for use with bit rates above 1 Mbit/s and up to 2 Mbit/s
Parameter Notation Value
Min Max
ns ns
Transmitted recessive bit width @ 2 Mbit/s t 435 530
Bit(Bus)
Received recessive bit width @ 2 Mbit/s t 400 550
Bit(RXD)
Receiver timing symmetry @ 2 Mbit/s Δt -65 +40
Rec

All requirements in this table apply concurrently. Therefore, not all combinations of t and Δt compli-

Bit(Bus) Rec
ant with t .
Bit(RXD)
Δt = t - t
Rec Bit(RXD) Bit(Bus)
Measurement setup according to Figure 2:
R = 60 Ω (tolerance ≤ ±1 %)
C = 0 pF (not present)
C = 100 pF (tolerance ≤ ±1 %)
C = 15 pF (tolerance ≤ ±1 %)
RXD
Measurement according to Figure 5:

The input signal on TXD shall have rise- and fall times (10 % / 90 %) of less than 10 ns.

Note: Limits for
...

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