IEC 60512-28-100:2024

IEC 60512-28-100 ®
Edition 3.0 2024-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Connectors for electrical and electronic equipment – Tests and measurements –
Part 28-100: Signal integrity tests up to 2 000 MHz – Tests 28a to 28g

Connecteurs pour équipements électriques et électroniques – Essais
et mesures –
Partie 28-100: Essais d’intégrité des signaux jusqu’à 2 000 MHz – Essais 28a
à 28g
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IEC 60512-28-100 ®
Edition 3.0 2024-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Connectors for electrical and electronic equipment – Tests and measurements –

Part 28-100: Signal integrity tests up to 2 000 MHz – Tests 28a to 28g

Connecteurs pour équipements électriques et électroniques – Essais

et mesures –
Partie 28-100: Essais d’intégrité des signaux jusqu’à 2 000 MHz – Essais 28a

à 28g
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.220.10 ISBN 978-2-8322-9504-5

– 2 – IEC 60512-28-100:2024 © IEC 2024

CONTENTS
FOREWORD . 6
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 10
3.1 Terms and definitions. 10
3.2 Abbreviated terms . 10
4 Overall test arrangement . 11
4.1 General . 11
4.2 Test instrumentation . 11
4.2.1 General . 11
4.2.2 Vector network analyser . 11
4.2.3 RF switching unit . 11
4.2.4 Reference loads and termination loads . 11
4.3 Measurement precautions . 12
4.4 Mixed mode S-parameter nomenclature . 12
4.5 Coaxial cables and interconnections for network analysers . 13
4.6 Characteristic for switching matrices . 14
4.7 Test fixture types . 14
4.8 Requirements for termination performance at calibration plane . 14
4.9 Reference loads for calibration . 14
4.10 Calibration . 15
4.10.1 General . 15
4.10.2 Calibration test interface . 16
4.10.3 Calibration at end of coaxial test cables . 16
4.11 Termination loads for termination of conductor pairs . 16
4.11.1 General . 16
4.11.2 Impedance matching resistor termination networks . 17
4.12 Termination of screens . 17
4.13 Test specimen and reference planes . 17
4.13.1 General . 17
4.13.2 Interconnections between the device under test (DUT) and the
calibration plane . 18
4.14 Overall test setup requirements . 19
5 Connector measurements up to 2 000 MHz . 20
5.1 General . 20
5.1.1 Determining pass and fail . 20
5.2 Insertion loss, test 28a . 20
5.2.1 Object . 20
5.2.2 Insertion loss . 20
5.2.3 Test method . 20
5.2.4 Test setup . 20
5.2.5 Procedure . 20
5.2.6 Test report . 21
5.2.7 Accuracy . 21
5.3 Return loss, test 28b . 22
5.3.1 Object . 22
5.3.2 Return loss . 22

5.3.3 Test method . 22
5.3.4 Test setup . 22
5.3.5 Procedure . 23
5.3.6 Test report . 23
5.3.7 Accuracy . 23
5.4 Near-end crosstalk (NEXT), test 28c . 23
5.4.1 Object . 23
5.4.2 NEXT. 23
5.4.3 Test method . 23
5.4.4 Test setup . 24
5.4.5 Procedure . 24
5.4.6 Test report . 25
5.4.7 Accuracy . 25
5.5 Far-end crosstalk (FEXT), test 28d . 25
5.5.1 Object . 25
5.5.2 FEXT . 25
5.5.3 Test method . 25
5.5.4 Test setup . 25
5.5.5 Procedure . 26
5.5.6 Test report . 26
5.5.7 Accuracy . 27
5.6 Transverse conversion loss (TCL), test 28f . 27
5.6.1 Object . 27
5.6.2 TCL . 27
5.6.3 Test method . 27
5.6.4 Test setup . 27
5.6.5 Procedure . 27
5.6.6 Test report . 28
5.6.7 Accuracy . 28
5.7 Transverse conversion transfer loss (TCTL), test 28g . 28
5.7.1 Object . 28
5.7.2 TCTL . 28
5.7.3 Test method . 28
5.7.4 Test setup . 28
5.7.5 Procedure . 28
5.7.6 Test report . 29
5.7.7 Accuracy . 29
5.8 Shield transfer impedance (Z ), test 26e . 29
T
5.8.1 Object . 29
5.8.2 Transfer impedance (Z ) . 29
T
5.8.3 Test method . 29
5.8.4 Test setup . 30
5.8.5 Procedure . 30
5.8.6 Test report . 30
5.8.7 Accuracy . 30
5.9 Coupling attenuation (a ) . 30
C
5.9.1 Object . 30
5.9.2 Coupling attenuation (a ) . 30
C
– 4 – IEC 60512-28-100:2024 © IEC 2024

5.9.3 Test method . 31
5.9.4 Test setup . 31
5.9.5 Procedure . 31
5.9.6 Test report . 31
5.9.7 Accuracy . 31
5.10 Low frequency coupling attenuation a . 31
CLF
5.10.1 Object . 31
5.10.2 Low frequency coupling attenuation (a ) . 32
CLF
5.10.3 Test method . 32
5.10.4 Test setup . 32
5.10.5 Procedure . 32
5.10.6 Test report . 32
5.10.7 Accuracy . 33
Annex A (informative) Derivation of mixed mode parameters using the modal
decomposition technique . 34
A.1 General . 34
A.2 Example of a calculation . 34
Annex B (normative) Indirect-reference test fixtures . 37
B.1 General . 37
B.2 Requirements . 37
B.2.1 General requirements . 37
B.2.2 Specific requirements . 37
Annex C (normative) Direct-probe test fixtures . 39
C.1 General . 39
C.2 Requirements . 39
C.2.1 General requirements . 39
C.2.2 Specific requirements . 39
Annex D (normative) Specialized test fixtures . 41
D.1 General . 41
D.2 Requirements . 41
D.2.1 General requirements . 41
D.2.2 Specific requirements . 41
Annex E (informative) Symmetry verification of resistors used for calibration . 42
E.1 General . 42
E.2 Procedure . 42
E.3 Example . 43
Bibliography . 45

Figure 1 – Diagram of a single-ended 4-port device . 12
Figure 2 – Diagram of a balanced 2-port device . 13
Figure 3 – Calibration of reference loads . 15
Figure 4 – Resistor termination networks . 16
Figure 5 – Definition of reference planes. 17
Figure 6 – Insertion loss and TCTL measurement . 21
Figure 7 – Return loss and TCL measurement . 22
Figure 8 – NEXT measurement . 24
Figure 9 – FEXT measurement . 26

Figure A.1 – Voltage and current on balanced DUT . 34
Figure A.2 – Voltage and current on unbalanced DUT . 35
Figure E.1 – Example of 50 Ω SMA termination comparison (1 MHz − 100 MHz). 43
Figure E.2 – Comparison of phase selected and only magnitude selected terminations . 44

Table 1 – Mixed mode S-parameter nomenclature . 13
Table 2 – Switch performance requirements . 14
Table 3 – Requirements for terminations at calibration plane . 14
Table 4 – Interconnection DM return loss and TCTL requirements . 19
Table 5 – Overall test setup requirements . 19
Table B.1 – [1] series 8-way connector types detail specifications and respective detail
connector test procedures standards . 37
Table B.2 – Reference connector crosstalk (NEXT) vector . 38
Table C.1 – Direct-probe test fixture requirements . 39

– 6 – IEC 60512-28-100:2024 © IEC 2024

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Connectors for electrical and electronic equipment –
Tests and measurements –
Part 28-100: Signal integrity tests up to 2 000 MHz – Tests 28a to 28g

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
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Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
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expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 60512-28-100 has been prepared by subcommittee 48B: Electrical connectors, of IEC
technical committee 48: Electrical connectors and mechanical structures for electrical and
electronic equipment. It is an International Standard.
This third edition cancels and replaces the second edition, published in 2019. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) The frequency range has been modified to start at 0,1 MHz instead of 1 MHz, to include
single-pair connectors.
b) All tables and requirements have been revised down to 0,1 MHz, and partially improved to
reduce the impact of the test fixture.
c) Formulae to calculate the S-parameters from single-ended parameters have been added.
d) A note was added for those parameters which are not applicable to single-pair connectors.
The text of this International Standard is based on the following documents:
FDIS Report on voting
48B/3109/FDIS 48B/3112/RVD
Full information on the voting for the 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.
A list of all parts in the IEC 60512 series, published under the general title Connectors for
electrical and electronic equipment, can be found on the IEC website.
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/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
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document 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.

– 8 – IEC 60512-28-100:2024 © IEC 2024

Connectors for electrical and electronic equipment –
Tests and measurements –
Part 28-100: Signal integrity tests up to 2 000 MHz – Tests 28a to 28g

1 Scope
This part of IEC 60512 specifies the test methods for signal integrity and transmission
performance for connectors specified in respective parts of IEC 60603-7 [1], IEC 61076-1 [2],
IEC 61076-2 [3], IEC 61076-3 [4] and IEC 63171 [5] series of standards for connecting hardware
applications from 0,1 MHz up to 2 000 MHz, with reference to this document.
NOTE This document is also suitable for testing signal integrity and transmission performance of connectors up to
a lower value of maximum frequency; however, the test methodology specified in the detail specification for any given
connector remains the reference conformance test for that connector.
The list of connector series of standards does not preclude referencing this document in other
connector manufacturer’s specifications or published standards.
Test procedures provided herein are:
– insertion loss, test 28a;
– return loss, test 28b;
– near-end crosstalk (NEXT) test 28c;
– far-end crosstalk (FEXT), test 28d;
– transverse conversion loss (TCL), test 28f;
– transverse conversion transfer loss (TCTL), test 28g.
Other test procedures referenced herein are:
– shield transfer impedance (Z ), see IEC 60512-26-100, test 26e.
T
– coupling attenuation (a ), see IEC 62153-4-7 and IEC 62153-4-12.
C
– low frequency coupling attenuation (a ) see IEC 62153-4-7 and IEC 62153-4-15.
CLF
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 60050-581, International Electrotechnical Vocabulary (IEV) – Part 581: Electromechanical
components for electronic equipment
IEC 60512-1, Connectors for electronic equipment – Tests and measurements – Part 1: Generic
specification
IEC 60512-26-100, Connectors for electronic equipment – Tests and measurements – Part
26-100: Measurement setup, test and reference arrangements and measurements for
connectors according to IEC 60603-7 – Tests 26a to 26g

IEC 60512-27-100, Connectors for electronic equipment – Tests and measurements –
Part 27-100: Signal integrity tests up to 500 MHz on 60603-7 series connectors – Tests 27a to
27g
IEC 60512-27-200, Connectors for electrical and electronic equipment – Tests and
measurements – Part 27-200: Additional specifications for signal integrity tests up to 2 000 MHz
on IEC 60603-7 series connectors – Tests 27a to 27g
IEC 60512-29-100, Connectors for electronic equipment – Tests and measurements –
Part 29-100: Signal integrity tests up to 500 MHz on M12 style connectors – Tests 29a to 29g
IEC 60603-7, Connectors for electronic equipment – Part 7: Detail specification for 8-way,
unshielded, free and fixed connectors
IEC 61076-1, Connectors for electronic equipment – Product requirements – Part 1: Generic
specification
IEC 61076-3-104, Connectors for electrical and electronic equipment – Product requirements –
Part 3-104: Detail specification for 8-way, shielded free and fixed connectors for data
transmissions with frequencies up to 2 000 MHz
IEC 61076-3-110, Connectors for electronic equipment – Product requirements – Part 3-110:
Detail specification for free and fixed connectors for data transmission with frequencies up to
3 000 MHz
IEC 61156-1, Multicore and symmetrical pair/quad cables for digital communications – Part 1:
Generic specification
IEC 61169-15, Radio-frequency connectors – Part 15: Sectional specification – RF coaxial
connectors with inner diameter of outer conductor 4,13 mm (0,163 in) with threaded coupling –
Characteristic impedance 50 Ω (type SMA)
IEC 61169-16, Radio-frequency connectors – Part 16: RF coaxial connectors with inner
diameter of outer conductor 7 mm (0,276 in) with screw coupling – Characteristic impedance
50 ohms (75 ohms) (Type N)
IEC 62153-4-6, Metallic cables and other passive components test methods – Part 4-6:
Electromagnetic compatibility (EMC) – Surface transfer impedance – Line injection method
IEC 62153-4-7, Metallic cables and other passive components test methods – Part 4-7:

Electromagnetic compatibility (EMC) – Test method for measuring of transfer impedance Z
T
and screening attenuation a or coupling attenuation aC of connectors and assemblies – Triaxial
S
tube in tube method
IEC 62153-4-12, Metallic communication cable test methods – Part 4-12: Electromagnetic
compatibility (EMC) – Coupling attenuation or screening attenuation of connecting hardware –
Absorbing clamp method
IEC 62153-4-15, Metallic cables and other passive components test methods – Part 4-15:
Electromagnetic compatibility (EMC) – Test method for measuring transfer impedance and
screening attenuation – or coupling attenuation with triaxial cell
IEC 63171, Connectors for electrical and electronic equipment – Shielded or unshielded free
and fixed connectors for balanced single-pair data transmission with current-carrying capacity
– General requirements and tests

– 10 – IEC 60512-28-100:2024 © IEC 2024

ISO/IEC 11801-1, Information technology – Generic cabling for customer premises – Part 1:
General requirements
3 Terms, definitions and abbreviated terms
For the purposes of this document, the terms and definitions given in IEC 60050-581,
IEC 61076-1, IEC 60512-1, IEC 60603-7, IEC 61076-3-104, IEC 61076-3-110, IEC 61156-1 and
IEC 63171, and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1 Terms and definitions
3.1.1
intermodal
parameter or measurement that either sources on the common
mode and measures on the differential mode, or sources on the differential mode and measures
on the common mode
3.1.2
mixed mode
parameter or measurement containing differential mode,
common mode, and intermodal S-matrices
3.1.3
interconnection
cable assembly made of a cable terminated by two connectors
EXAMPLE: A connection between a VNA, switching matrix or test fixture
3.2 Abbreviated terms
a coupling attenuation
C
a Low frequency coupling attenuation
CLF
CM common mode
DM differential mode
DUT device under test
FEXT far-end crosstalk loss
LCL longitudinal conversion loss
LCTL longitudinal conversion transfer loss
NEXT near-end crosstalk loss
RF radio frequency
RL return loss, common mode
CM
RL return loss, differential mode
DM
SE single-ended
TCL transverse conversion loss
TCTL transverse conversion transfer loss
VNA vector network analyser
Z transfer impedance
T
4 Overall test arrangement
4.1 General
This document specifies test methods and procedures for connectors.
The test methods and procedures for signal integrity and transmission performance specified
herein are referenced by connector standards, specified in IEC 60603-7 [1], IEC 61076-1 [2],
IEC 61076-2 [3], IEC 61076-3 [4], IEC 63171 [5] series of standards and other standards for
connecting hardware and their sectional specifications, with signal integrity specifications from
0,1 MHz up to 2 000 MHz; such connector standards include IEC 60603-7-81 [6], IEC 60603-7-
82 [7], IEC 61076-3-110 [8], IEC 61076-3-104 [9], and IEC 61076-2-109 [10]. They are used
with twisted-pair or quad cables having 100 Ω nominal differential characteristic impedance,
which are specified in accordance with IEC 61156 (all parts) [11] and its sectional specifications
covering at least the frequency range supported by the connecting hardware.
4.2 Test instrumentation
4.2.1 General
All test instrumentation shall be capable of performing measurements over the frequency range
of 0,1 MHz to 2 000 MHz or at least the frequency range of the connector under test.
4.2.2 Vector network analyser
The VNA shall have a minimum of two ports (including one bi-directional port) to enable the
data to be collated and calculated.
A 4-port VNA is recommended as a practical minimum number of ports, as this will allow the
measurement of the full 16-term mixed mode S-parameter matrix on a given pair or pair
combination without switching or reconnection, as shown in Figure 6, Figure 7, Figure 8 and
Figure 9.
The use of a 2-port VNA will involve successive repositioning of the measurement port in order
to measure any given parameter. For single-pair connectors a 4-port VNA is recommended to
be used to measure all S-parameter combinations to avoid external switching. For 4-pair
devices, a 16-port VNA is recommended to be used to measure all S-parameter combinations
to avoid external switching.
4.2.3 RF switching unit
In order to minimize the reconnection of the DUT for each pair combination the use of a RF
switching unit is also recommended.
Each conductor of the pair or pair combination under test shall be connected to a separate port
of the VNA, and results are processed either by internal analysis within the VNA or by an
external application.
4.2.4 Reference loads and termination loads
Reference loads and through connections shall be utilised for the calibration of the setup.
Requirements for the reference loads shall be as given in 4.9. Termination loads shall be utilised
for termination of pairs, used and unused, which are not terminated by the VNA. Requirements
for the termination loads shall be as given in 4.11.
Loads used for calibration shall be paired as explained in Annex E to ensure good symmetry at
the calibration plane.
– 12 – IEC 60512-28-100:2024 © IEC 2024

4.3 Measurement precautions
To ensure a high degree of reliability for transmission measurements, the following precautions
are required.
• Resistors with a tolerance of ±0,1 % shall be used throughout the test sequence.
• Cable and adapter discontinuities, as introduced by physical flexing, sharp bends and
restraints shall be avoided before, during and after the tests.
• Standardised test methodology and termination resistors shall be used at all stages of
transmission performance qualifications.
• The balance of the cables shall be maintained to the greatest extent possible by ensuring
same conductor lengths and pair twisting to the point of load.
• The relative spacing of conductors in the pairs shall be preserved throughout the tests to
the greatest extent possible.
• The sensitivity to setup variations for these measurements at high frequencies demands
attention to details for both the measurement equipment and the procedures.
• The test setup shall be appropriately earthed (bonded).
4.4 Mixed mode S-parameter nomenclature
The test methods specified in this document are based on a balunless test setup in which all
terminals of a device under test are measured and characterised as single-ended (SE) ports,
i.e. signals (RF voltages and currents) shall be defined relative to a common earth (ground)
plane. For a device with four terminals, a diagram is given in Figure 1.

Figure 1 – Diagram of a single-ended 4-port device
The 4-port device in Figure 1 shall be characterised by the 16-term SE S-matrix given in
Formula (1), in which the S-parameter S expresses the relation between a single-ended
ba
response on port “b” resulting from a single-ended stimulus on port “a”.
𝑆𝑆 𝑆𝑆 𝑆𝑆 𝑆𝑆
11 12 13 14
𝑆𝑆 𝑆𝑆 𝑆𝑆 𝑆𝑆
21 22 23 24
𝑆𝑆 =� � (1)
𝑆𝑆 𝑆𝑆 𝑆𝑆 𝑆𝑆
31 32 33 34
𝑆𝑆 𝑆𝑆 𝑆𝑆 𝑆𝑆
41 42 43 44
For a balanced device, each port shall be considered to consist of a pair of terminals (= a
balanced port) as opposed to the SE ports defined above, see Figure 2.

a balanced
Figure 2 – Diagram of a balanced 2-port device
The device is characterised by a mixed mode S-matrix that includes all combinations of modes
and ports, for example the mixed mode S-parameter S that expresses the relation between
DC21
a differential mode response on port 2 resulting from a common mode stimulus on port 1. Using
this nomenclature, the full set of mixed mode S-parameters for a 2-port device are given in
Table 1.
Table 1 – Mixed mode S-parameter nomenclature
Differential mode stimulus Common mode stimulus
Port 1 Port 2 Port 1 Port 2
Differential mode response Port 1 S S S S
DD11 DD12 DC11 DC12
Port 2 S S S S
DD21 DD22 DC21 DC22
Common mode response Port 1 S S S S
CD11 CD12 CC11 CC12
Port 2 S S S S
CD21 CD22 CC21 CC22
A 4-terminal device can be represented both as a 4-port SE device as in Figure 1 characterised
by a single-ended S-matrix (Formula (1)) and as a 2-port balanced device as in
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