IEC 62783-1-1:2022

Twinax cables for digital communications - Part 1-1: Time domain test methods for twinax cables for digital communications - General requirements

IEC 62783-1-1:2022 specifies time domain test methods, parameters and requirements for fixtures for twinax cables (known also as twin-axial cables or twin-coaxial cables) used in digital communication systems. The methods and fixtures facilitate measurements of differential and common mode transmission parameters as well as single-ended mode parameters. This document is applicable to twinax cables and also to symmetric cables with pitch.

General Information

• Status: Published
• Publication Date: 16-Jun-2022
• ICS: 33.120.20 - Wires and symmetrical cables
• Technical Committee: SC 46C - Wires and symmetric cables
• Drafting Committee: WG 10 - TC 46/SC 46C/WG 10
• Current Stage: PPUB - Publication issued
• Start Date: 15-Jul-2022
• Completion Date: 17-Jun-2022

Standards Content (Sample)

IEC 62783-1-1 ®
Edition 1.0 2022-06
INTERNATIONAL
STANDARD
colour
inside
Twinax cables for digital communications –
Part 1-1: Time domain test methods for twinax cables for digital
communications – General requirements
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IEC 62783-1-1 ®
Edition 1.0 2022-06
INTERNATIONAL
STANDARD
colour
inside
Twinax cables for digital communications –

Part 1-1: Time domain test methods for twinax cables for digital

communications – General requirements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.120.20 ISBN 978-2-8322-3853-0

– 2 – IEC 62783-1-1:2022 © IEC 2022
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 6
3.1 Terms and definitions . 6
3.2 Abbreviated term . 8
4 Test equipment . 8
4.1 Measurement equipment . 8
4.2 Coaxial cables (test leads) . 8
4.3 Test fixtures . 9
4.4 Termination resistors . 9
4.5 Through calibration kit (Thru kit) . 9
5 Test conditions . 9
6 Measurement methods . 10
6.1 Calibration . 10
6.2 De-skew . 10
6.3 Establish the reference plane for the TDR measurement . 10
6.4 Establish the reference plane for the TDT measurement . 11
6.5 Measurement . 11
7 Test report . 11
Bibliography . 12

Figure 1 – Test schematic diagram for open location of the test fixture . 10
Figure 2 – Test schematic diagram for TDT measurement . 11

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TWINAX CABLES FOR DIGITAL COMMUNICATIONS –

Part 1-1: Time domain test methods for twinax cables
for digital communications – General requirements

FOREWORD
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IEC 62783-1-1 has been prepared by subcommittee 46C: Wires and symmetric cables, of IEC
technical committee 46: Cables, wires, waveguides, RF connectors, RF and microwave passive
components and accessories. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
46C/1191/CDV 46C/1218/RVC
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.

– 4 – IEC 62783-1-1:2022 © IEC 2022
This document was drafted in accordance with ISO/IEC Directives, Part 2, and 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/standardsdev/publications.
A list of all parts in the IEC 62783 series, published under the general title Twinax cables for
digital communications, can be found on the IEC website.
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
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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INTRODUCTION
This document specifies the general requirements of time domain test methods for twinax
cables used in information technology systems. The high data rates of these systems need both
frequency domain test methods and time domain test methods to ensure signal integrity.
Time domain here refers to time domain analysis or display(s), as defined by an X-Y graph
where the X-axis is either time or electrical length of device under test (DUT), and the Y-axis is
magnitude (voltage, impedance or reflection coefficient). Time domain display provides a direct
view of the DUT's characteristics. In addition, time domain method gives information concerning
the reflection and transmission of the DUT and it can show the effect of each discontinuity as a
function of time or distance.
– 6 – IEC 62783-1-1:2022 © IEC 2022
TWINAX CABLES FOR DIGITAL COMMUNICATIONS –

Part 1-1: Time domain test methods for twinax cables
for digital communications – General requirements

1 Scope
This part of IEC 62783-1 specifies time domain test methods, parameters and requirements for
fixtures for twinax cables (known also as twin-axial cables or twin-coaxial cables) used in digital
communication systems. The methods and fixtures facilitate measurements of differential and
common mode transmission parameters as well as single-ended mode parameters.
This document is applicable to twinax cables and also to symmetric cables with pitch.
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.
IEC 60050-726, International Electrotechnical Vocabulary (IEV) – Part 726: Transmission lines
and waveguides (available at www.electropedia.org)
IEC 62783-1, Twinax cables for digital communications – Part 1: Generic specification
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-726,
IEC 62783-1 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• ISO Online browsing platform: available at http://www.iso.org/obp
• IEC Electropedia: available at http://www.electropedia.org/
3.1.1
time domain reflectometer
TDR
instrument intended to measure reflections and transmissions of step pulse waves along the
device under test (DUT), the individual reflections being measured and displayed as a function
of time or distance
3.1.2
rise time
time interval between the instants at which the magnitude of the pulse first reaches a specified
lower value and then a specified upper value
Note 1 to entry: In general, ignoring overshoot and undershoot, the lower level and upper level of pulse magnitude
are specified at 10 % to 90 %, unless otherwise specified.

IEC 62783
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