1、 EIA STANDARD TP-103 Propagation Delay Test Procedure for Electrical Connectors, Sockets, CableAssemblies or Interconnection Systems EIA-364-103February 1999 ELECTRONIC COMPONENTS, ASSEMBLIES see figure 1.1.2.2 Specimen environment impedanceThe impedance presented to the signal conductors by the fix
2、ture. This impedance is a result oftransmission lines, termination resistors, attached receivers or signal sources, and fixtureparasitics.1.2.3 Propagation delayThe time required for a signal to travel between two specified points of an interconnect system;see figure 2.1.2.4 Termination (electronics
3、 usage)An impedance connected to the end of a transmission line, typically to minimize reflected energyon the line.EIA-364-103Page 22 Test resources2.1 Equipment2.1.1 Pulse generator and oscilloscope, TDR or other suitable equipment with a measurementsystem rise time less than or equal to the measur
4、ed propagation delay.2.1.2 ProbesProbes, where applicable, shall have suitable rise time performance and circuit loadingcharacteristics (resistance and capacitance).2.2 MaterialWhen the fixture is a printed circuit board, the reference trace and the test trace should be madeon the same printed circu
5、it board to reduce any difference in PCB fabrication processes, dielectricmaterial variations, etc.2.3 FixtureUnless otherwise specified in the referencing document the specimen environment impedance shallmatch the impedance of the test equipment. Typically this will be 50 ohms for single-endedmeasu
6、rements and 100 ohms for differential.2.3.1 Method A, single-endedThe fixture shall allow one signal line to be driven at a time. The driven line shall be terminatedaccording to one of the methods of figure A.2 with the specimen environment impedance. Unlessotherwise specified a 1:1 signal to ground
7、 ratio shall be used with each end having all groundscommoned. Each line adjacent to the driven line(s) shall also be terminated in the specimenenvironment impedance at both near and far ends.2.3.1.1 Probe techniqueThe fixture shall be designed to allow the signal to be probed at the two points betw
8、een which thedelay is to be measured; see figure A.1.a.2.3.1.2 Insertion techniqueThe fixture shall be designed to allow measurement of propagation delay with and without thespecimen; see figure A.1.b.EIA-364-103Page 32.3.1.3 Reference fixture techniqueTwo fixtures shall be designed that include the
9、 same fixture electrical length and characteristics ofenvironment transmission line. The “specimen fixture” includes the specimen. The “referencefixture” does not include the specimen. The fixture electrical length does not include thespecimen length; see figure A.1.c.2.3.2 Method B, differentially
10、drivenThe fixture shall allow one signal pair to be driven at a time. The driven line shall be terminatedaccording to one of the methods of figure A.3 with the specimen environment impedance. Unlessotherwise specified a 2:1 signal to ground ratio shall be used. Each line adjacent to the drivenline(s
11、) shall also be terminated in the specimen environment impedance at both near and far ends.2.3.2.1 Probe techniqueThe fixture shall be designed to allow the signal pair to be probed at the points between which thedelay is to be measured; see figure A.1.a.2.3.2.2 Insertion techniqueThe fixture shall
12、be designed to allow measurement of propagation delay with and without thespecimen; see figure A.1.b.2.3.2.3 Reference fixture techniqueTwo fixtures shall be designed that include the same fixture electrical length and characteristics ofthe environment transmission line. The “specimen fixture” inclu
13、des the specimen. The “referencefixture” does not include the specimen. The fixture electrical length does not include thespecimen length; see figure A.1.c.3 Test Specimen3.1 DescriptionFor this test procedure the test specimen shall be as follows:3.1.1 Separable connectorsA mated connector pair.3.1
14、.2 Cable assemblyAssembled connectors and cables, and mated connectors.3.1.3 SocketsEIA-364-103Page 4A socket and test device or a socket and pluggable header adapter.4 Test procedureUnless otherwise specified the measurement system rise time shall be less than or equal to themeasured delay. The mea
15、surement system rise times specified in table 1 are recommended. Thethree techniques below apply to single-ended and differential measurements. For differentialmeasurements, it is necessary to determine whether any phase and/or amplitude errors existbetween the probe/channels and to provide necessar
16、y compensation for these errors so that eachstep arrives at the specimen simultaneously. Two measurements shall be performed as described in4.2 or 4.3 and the time difference recorded; see figure 2 and A.1. Unless otherwise specified, forall three techniques the delay shall be measured at both the 1
17、0% and 50% amplitudes. Place thespecimen a minimum of 5 cm from any object that would affect measured results.NOTES1 The test professional should be aware of limitations of any math operation(s) performedby an instrument, (e.g. normalization or software filtering).2 Specimen induced skew shall not b
18、e compensated. When skew is observed a waveformplot shall be provided.3 The input and output step amplitudes may not be equal due to attenuation in the deviceunder test. When this occurs, the output step 10% and 90% levels are to be referencedfrom the maximum output voltage, regardless of what volta
19、ge was put in.Table 1 - Recommended measurement system rise time (including fixture and filtering)Measured (expected) propagation delay of the specimen,picosecondsMeasurement system rise time,picoseconds100 500 100500 - 1,000 500 1,000 10004.1 Probe techniqueMeasure the time difference between the i
20、nput and output voltages. This is the propagation delay.4.2 Insertion techniqueMeasure the time difference of the output voltage with and without the specimen. This is thepropagation delay.EIA-364-103Page 54.3 Reference fixture techniqueMeasure the time difference between the “reference fixture” and
21、 the “specimen fixture”. This isthe propagation delay.5 Details to be specifiedThe following details shall be specified in the referencing document:5.1 Measurement system rise time, if other than specified in table 15.2 Termination value (and tolerances)5.3 Signal/ground pattern, including the numbe
22、r and location of signal and grounds to be wiredfor this test. It is recommended that the specimen locations represent the maximum and minimumdelays.5.4 Points between which the delay shall be measured.5.5 Specimen environment impedance if other than 50 ohms for single-ended and 100 ohms fordifferen
23、tial.6 Test documentationDocumentation shall contain the details specified in clause 5, with any exceptions, and thefollowing:6.1 Title of test6.2 Test equipment used, and date of last and next calibration6.3 Test procedure and method6.4 Fixture description6.5 Measurement system rise time (including
24、 fixture and filtering, 10% to 90%)6.6 Measured propagation delay(s)6.7 Waveform plots (when required); see clause 4, note 26.8 Observations6.9 Name of operator and date of testEIA-364-103Page 6Figure 1 - Rise time measurement pointsNOTE Ignore overshoot and undershoot when calculating 0% and 100% l
25、evels.Figure 2 - Propagation delay measurement pointsEIA-364-103Page A- 1AnnexA NormativeFigure A.1.a - Probe techniqueFigure A.1.b - Insertion techniqueFigure A.1.c - Reference fixture techniqueFigure A.1 - Technique diagramsEIA-364-103Page A- 2Minimum loss pad equations:R 1 = 50 1 - (Z o / 50) 0.5
26、 R 1 = Z o 1 - (50 / Z o ) 0.5R 2 = Z o / 1 - (Z o / 50) 0.5 R 2 = 50 / 1 - (50 / Z o ) 0.5Figure A.2 - Single-ended terminationsEIA-364-103Page A- 3Minimum loss pad equations:R 1 = Z o 1 - (100 / Z o ) 0.5 / 2 R 1 = 100 1 - (Z o / 100) 0.5 / 2R 2 = 100 / 1 - (100 / Z o ) 0.5 R 2 = Z o / 1 - (Z o /
27、100) 0.5Figure A.3 - Differential (balanced) terminationsEIA-364-103Page B- 1B InformativeB.1 Practical guidanceNear perfect resistive terminations of the signal lines may not be possible at high frequencies dueto parasitic reactances in both signal and ground conductors. These reactances will have
28、animpact on measured results. In this case it is desirable that the test fixture duplicate the exactgeometry (parasitics) of the actual application. This may involve the use of transmission lines inaddition to the components of figures A.1 and A.2. Most instruments used for thesemeasurements are int
29、ernally terminated in 50 ohms at both source and detector ports.EIA Document Improvement ProposalIf in the review or use of this document, a potential change is made evident for safety, health or technicalreasons, please fill in the appropriate information below and mail or FAX to:Electronic Compone
30、nts Industry AssociationEngineering Department Publications Office4212 Rock Hill Road, Suite 170Herndon, VA 20170-4212Phone: (571) 323-0294Document No. Document Title:Submitters Name: Telephone No.:FAX No.:e-mail:Address:Urgency of Change:Immediate: At next revision:Problem Area:a. Clause Number and/or Drawing:b. Recommended Changes:c. Reason/Rationale for Recommendation:Additional Remarks:Signature: Date:FOR EIA USE ONLYResponsible Committee:Chairman:Date comments forwarded to Committee Chairman:
