1、BRITISH STANDARD BS EN 60512-25-4: 2001 IEC 60512-25-4: 2001 Connectors for electronic equipment Tests and measurements Part 25-4: Test 25d Propagation delay The European Standard EN 60512-25-4:2001 has the status of a British Standard ICS 31.220.10 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMIT
2、TED BY COPYRIGHT LAWBS EN 60512-25-4:2001 This British Standard, having been prepared under the direction of the Electrotechnical Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 19 November 2001 BSI 19 November 2001 ISBN 0 580
3、 38670 8 National foreword This British Standard is the official English language version of EN 60512-25-4:2001. It is identical with IEC 60512-25-4:2001 The UK participation in its preparation was entrusted by Technical Committee EPL/48, Electromechanical components for electronic equipment, to Sub
4、committee EPL/48/2, Connectors for electronic equipment, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. From 1 January 1997, all IEC publications have the number 60000 added to the old number. For instance, IEC 2
5、7-1 has been renumbered as IEC 60027-1. For a period of time during the change over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references The British Standards which implement international or European publications referred to in this docume
6、nt may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of Bri
7、tish Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or propos
8、als for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 12, an inside back cover and a back cover. The BSI c
9、opyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEAN STANDARD EN 60512-25-4 NORME EUROPENNE EUROPISCHE NORM October 2001 CENELEC European Committee for Electrotechnical Standardization Comit Europen d
10、e Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2001 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60512-25-4:2001 E ICS 31.220.10 Engl
11、ish version Connectors for electronic equipment - Tests and measurements Part 25-4: Test 25d - Propagation delay (IEC 60512-25-4:2001) Connecteurs pour quipements lectroniques - Essais et mesures Partie 25-4: Essai 25d - Retard de propagation (CEI 60512-25-4:2001) Steckverbinder fr elektronische Ein
12、richtungen - Mess- und Prfverfahren Teil 25-4: Prfung 25d - Laufzeitverzgerung (IEC 60512-25-4:2001) This European Standard was approved by CENELEC on 2001-10-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Sta
13、ndard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, Fr
14、ench, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium
15、, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.Foreword The text of document 48B/1061/FDIS, future edition 1 of IEC 60512-25-4, prepared by SC 48B, Connectors, of IE
16、C TC 48, Electromechanical components and mechanical structures for electronic equipment, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60512-25-4 on 2001-10-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by
17、publication of an identical national standard or by endorsement (dop) 2002-07-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2004-10-01 Annexes designated “normative“ are part of the body of the standard. Annexes designated “informative“ are given f
18、or information only. In this standard, annex A is normative and annex B is informative. _ Endorsement notice The text of the International Standard IEC 60512-25-4:2001 was approved by CENELEC as a European Standard without any modification. _ Page 2 EN 60512254:2001 BSI 19 November 2001CONTENTS 1 Ge
19、neral . 4 1.1 Scope and object 4 1.2 Definitions 4 2 Test resources.4 2.1 Equipment 4 2.2 Fixture 5 2.2.1 Method A, single-ended 5 2.2.2 Method B, differentially driven. 5 3 Test specimen . 6 3.1 Description . 6 3.1.1 Separable connectors . 6 3.1.2 Cable assembly 6 3.1.3 Sockets. 6 4 Test procedure
20、6 4.1 Probe technique . 6 4.2 Insertion technique . 7 4.3 Reference fixture technique 7 5 Details to be specified . 7 6 Test documentation . 7 Annex A (normative) Diagrams and schematics of fixtures and equipment 9 Annex B (informative) Practical guidance .12 Figure 1 Rise time measurement points. 8
21、 Figure 2 Propagation delay measurement points. 8 Figure A.1 Technique diagrams. 9 Figure A.2 Single-ended terminations.10 Figure A.3 Differential (balanced) terminations.11 Table 1 Recommended measurement system rise time (including fixture and filtering) 6 Page 3 EN 60512254:2001 BSI 19 November 2
22、001CONNECTORS FOR ELECTRONIC EQUIPMENT TESTS AND MEASUREMENTS Part 25-4: Test 25d Propagation delay 1 General 1.1 Scope and object This part of IEC 60512 applies to electrical connectors, sockets, cable assemblies or inter- connection systems. This standard describes a method for measuring the time
23、it takes for a digital signal to propagate from one specified point to a second specified point. 1.2 Definitions For the purpose of this part of IEC 60512, the following definitions apply. 1.2.1 measurement system rise time rise time measured with the fixture in place, without the specimen, and with
24、 filtering (or normalization). Rise time is typically measured from 10 % to 90 % levels; see figure 1 1.2.2 specimen environment impedance impedance presented to the signal conductors by the fixture. This impedance is a result of transmission lines, termination resistors, attached receivers or signa
25、l sources, and fixture parasitics 1.2.3 propagation delay time required for a signal to travel between two specified points of an interconnect system; see figure 2 2 Test resources 2.1 Equipment 2.1.1 Pulse generator and oscilloscope, time domain reflectometer (TDR) or other suitable equipment with
26、a measurement system rise time less than or equal to the measured propagation delay. 2.1.2 Probes Probes, where applicable, shall have suitable rise time performance and circuit loading characteristics (resistance and capacitance). Page 4 EN 60512254:2001 BSI 19 November 20012.2 Fixture Unless other
27、wise specified in the reference document, the specimen environment impedance shall match the impedance of the test equipment. Typically, this will be 50 for single-ended measurements and 100 for differential. 2.2.1 Method A, single-ended The fixture shall allow one signal line to be driven at a time
28、. The driven line shall be terminated according to one of the methods of figure A.2 with the specimen environment impedance. Unless otherwise specified, a 1:1 signal-to-ground ratio shall be used with each end having all grounds commoned. Each line adjacent to the driven line(s) shall also be termin
29、ated in the specimen environment impedance at both near and far ends. 2.2.1.1 Probe technique The fixture shall be designed to allow the signal to be probed at the two points between which the delay is to be measured; see figure A.1a. 2.2.1.2 Insertion technique The fixture shall be designed to allo
30、w measurement of propagation delay with and without the specimen; see figure A.1b. 2.2.1.3 Reference fixture technique Two fixtures shall be designed that include the same fixture electrical length and character- istics of environment transmission line. The “specimen fixture” includes the specimen.
31、The “reference fixture” does not include the specimen. The fixture electrical length does not include the specimen length; see figure A.1c. 2.2.2 Method B, differentially driven The fixture shall allow one signal pair to be driven at a time. The driven line shall be terminated according to one of th
32、e methods of figure A.3 with the specimen environment impedance. Unless otherwise specified, a 2:1 signal-to-ground ratio shall be used. Each line adjacent to the driven line(s) shall also be terminated in the specimen environment impedance at both near and far ends. 2.2.2.1 Probe technique The fixt
33、ure shall be designed to allow the signal pair to be probed at the points between which the delay is to be measured; see figure A.1a. 2.2.2.2 Insertion technique The fixture shall be designed to allow measurement of propagation delay with and without the specimen; see figure A.1b. 2.2.2.3 Reference
34、fixture technique Two fixtures shall be designed that include the same fixture electrical length and characteristics of the environment transmission line. The “specimen fixture” includes the specimen. The “reference fixture” does not include the specimen. The fixture electrical length does not inclu
35、de the specimen length; see figure A.1c. Page 5 EN 60512254:2001 BSI 19 November 20013 Test specimen 3.1 Description For this test procedure, the test specimen shall be as follows. 3.1.1 Separable connectors A mated connector pair. 3.1.2 Cable assembly Assembled connectors and cables, and mated conn
36、ectors. 3.1.3 Sockets A socket and test device or a socket and pluggable header adaptor. 4 Test procedure Unless otherwise specified, the measurement system rise time shall be less than or equal to the measured delay. The measurement system rise times specified in table 1 are recom- mended. The thre
37、e techniques below apply to single-ended and differential measurements. For differential measurements, it is necessary to determine if any phase and/or amplitude errors exist between the probe/channels and to provide necessary compensation for these errors so that each step arrives at the specimen s
38、imultaneously. Two measurements shall be performed as described in 4.2 or 4.3 and the time difference recorded; see figure 2 and figure A.1. Unless otherwise specified, for all three techniques the delay shall be measured at both the 10 % and 50 % amplitudes. Place the specimen a minimum of 5 cm fro
39、m any object that would affect measured results. NOTE 1 The test professional should be aware of limitations of any mathematical operation(s) performed by an instrument (e.g. normalization or software filtering). NOTE 2 Specimen induced skew should not be compensated. When skew is observed, a wavefo
40、rm plot should be provided. NOTE 3 The input and output step amplitudes may not be equal, due to attenuation in the device under test. When this occurs, the output step 10 % and 90 % levels are referenced from maximum output voltage, regardless of what voltage was put in. Table 1 Recommended measure
41、ment system rise time (including fixture and filtering) Measured (expected) propagation delay of the specimen ps Measurement system rise time ps 100 500 100 500 1 000 500 1 000 1 000 4.1 Probe technique Measure the time difference between the input and output voltages. This is the propagation delay.
42、 Page 6 EN 60512254:2001 BSI 19 November 20014.2 Insertion technique Measure the time difference of the output voltage with and without the specimen. This is the propagation delay. 4.3 Reference fixture technique Measure the time difference between the “reference fixture” and the “specimen fixture”.
43、 This is the propagation delay. 5 Details to be specified The following details shall be specified in the reference document. 5.1 Measurement system rise time, if other than specified in table 1. 5.2 Termination value (and tolerances). 5.3 Signal/ground pattern, including the number and location of
44、signal and grounds to be wired for this test. It is recommended that the specimen locations represent the maximum and minimum delays. 5.4 Points between which the delay shall be measured. 5.5 Specimen environment impedance if other than 50 for single-ended and 100 for differential. 6 Test documentat
45、ion Documentation shall contain the details specified in clause 5, with any exceptions, and the following. 6.1 Title of test. 6.2 Test equipment, and date of last and next calibration. 6.3 Test procedure and method. 6.4 Fixture description. 6.5 Measurement system rise time (including fixture and fil
46、tering, 10 % to 90 %). 6.6 Measured propagation delay(s). 6.7 Waveform plots (when required); see clause 4, note 2. 6.8 Observations. 6.9 Name of operator and date of test. Page 7 EN 60512254:2001 BSI 19 November 200190 % V in 90 % V out 100 % V in 100 % V out 10 % V out 10 % V in Input rise time In
47、put waveform Output rise time Output waveform IEC 1193/01 Components V in input voltage V out output voltage Figure 1 Rise time measurement points Input waveform Output waveform t d(10 %) 50 % V in 50 % V out 100 % V in 100 % V out t d(50 %) 10 % V in 10 % V out IEC 1187/01 Components V in input vol
48、tage V out output voltage t d time, distance NOTE Ignore overshoot and undershoot when calculating 0 % and 100 % levels. Figure 2 Propagation delay measurement points Page 8 EN 60512254:2001 BSI 19 November 2001Annex A (normative) Diagrams and schematics of fixtures and equipment Source Termination
49、Probe 2 Probe 1 Source Specimen fixture A Specimen Specimen fixture B IEC 1194/01 Figure A.1a Probe technique Source Specimen fixture A Specimen Specimen fixture B Receiver Source Specimen fixture A Specimen fixture B Receiver IEC 1188/01 Figure A.1b Insertion technique Source Reference fixture (without specimen) Receiver Source Specimen fixture (with specimen) Receiver IEC 1189/01 Figure A.1c Reference fixture technique Figure A.1 Technique diagrams Page 9 EN 60512254:2