1、 EIA STANDARD TP-101 Attenuation Test Procedure for Electrical Connectors, Sockets, Cable Assemblies or Interconnection Systems EIA-364-101 May 2000 ANSI/EIA-364-101-2000(R2013) Approved: March 10, 2000 Reaffirmed: January 15, 2013 EIA-364-101 NOTICE EIA Engineering Standards and Publications are de
2、signed to serve the public interest through eliminating misunderstandings between manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existence
3、 of such Standards and Publications shall not in any respect preclude any member or nonmember of ECIA from manufacturing or selling products not conforming to such Standards and Publications, nor shall the existence of such Standards and Publications preclude their voluntary use by those other than
4、ECIA members, whether the standard is to be used either domestically or internationally. Standards and Publications are adopted by ECIA in accordance with the American National Standards Institute (ANSI) patent policy. By such action, ECIA does not assume any liability to any patent owner, nor does
5、it assume any obligation whatever to parties adopting the Standard or Publication. This EIA Standard is considered to have International Standardization implication, but the International Electrotechnical Commission activity has not progressed to the point where a valid comparison between the EIA St
6、andard and the IEC document can be made. This Standard does not purport to address all safety problems associated with its use or all applicable regulatory requirements. It is the responsibility of the user of this Standard to establish appropriate safety and health practices and to determine the ap
7、plicability of regulatory limitations before its use. (From Standards Proposal No. 4153-A, formulated under the cognizance of the EIA CE-2.0 National Connector Standards Committee and reaffirmed per Standards Proposal No. 5253.05). Published by Electronic Components Industry Association 2013 EIA Sta
8、ndards see figure A.1.a. If baluns are used for a measurement, or minimum loss pads used for impedance matching, these are included in the fixture. Figures A.2 and A.3. show typical configurations with minimum loss pads. 2.2.4 Reference fixture technique In this technique a separate fixture that com
9、bines both near end and far end is used for the fixture attenuation measurement; see figure A.1.b. This fixture shall be a duplicate of the specimen fixture, only without the specimen. Traces, if used, shall include fixture connectors, vias, bends, and corners. If baluns are used for a differential
10、measurement, or minimum loss pads used for impedance matching, these are included in the fixturing. Figures A.2 and A.3. show typical configurations with minimum loss pads. 3 Test Specimen 3.1 Description For this test procedure the test specimen shall be as follows: NOTE As the specimen length appr
11、oaches wavelength, careful interpretation of the results is required due to possible resonance effects. It is recommended t hat the specimen electrical length be 1/8 the wavelength of the maximum test frequency. 3.1.1 Separable connectors A mated pair with identified signals and grounds. 3.1.2 Cable
12、 assembly Assembled connectors and cable, and mating connector(s) with identified signal and ground contacts and wires. 3.1.3 Sockets A socket and test device or a socket and pluggable header adapter with identified signal and grounds. EIA-364-101 Page 4 4 Test procedure Unless otherwise specified a
13、ll measurement results shall contain a minimum of 200 frequency points. Each fixture measurement and its associated specimen attenuation measurement shall be taken at the same frequencies. Generate a magnitude versus frequency plot; 1 dB per division vertical scale and log frequency sweep are recomm
14、ended. When applicable, single frequency results shall be tabulated, as specified in the referencing document. Place the specimen a minimum of 5 cm from any objects that would affect measured results. NOTE The test professional should be aware of limitations of any math operation performed by an ins
15、trument, (e.g. normalization or software filtering). 4.1 Fixture attenuation Fixture attenuation shall be measured separately so that it can be removed from and compared to the specimen measurement. If the referencing document precisely specifies the fixture so that its attenuation contribution is f
16、ixed, then the fixture attenuation measurement is optional. NOTES Results may be inaccurate when: 1 The fixture attenuation is greater than the specimen attenuation. 2 The fixture electrical length is greater than 1/8 wavelength at the highest test frequency, unless special precautions are taken to
17、ensure good impedance matching throughout the measurement path. This can be confirmed by sweeping across a wide frequency range and observing if there are nulls due to moding, fixture or balun resonances, etc. 4.2 Method A, frequency domain 4.2.1 Network or spectrum analyzer (direct technique) 4.2.1
18、.1 Calibration 4.2.1.1.1 When using a network analyzer, at a minimum, a “through“ calibration at the reference plane (include analyzer cables but not specimen fixture) shall be performed. Where possible a 12 term calibration is recommended. 4.2.1.1.2 When using a spectrum analyzer and signal generat
19、or, take a reference measurement similarly. The generator output shall be kept the same for both fixture and specimen-with-fixture attenuation measurements made later. EIA-364-101 Page 5 4.2.1.2 Insertion technique 4.2.1.2.1 Assemble the fixture so that the near end is connected to the far end witho
20、ut the specimen in between; see figure A.1.a. Connect the network analyzer ports, or the signal generator and spectrum analyzer, to the appropriate locations of the driven line fixture. 4.2.1.2.2 When using a network analyzer measure the fixture attenuation (S21). 4.2.1.2.3 When using a spectrum ana
21、lyzer, measure the power from the generator through the fixture. Then divide the magnitude of this signal by that of the reference measurement performed in 4.2.1.1.2 at each frequency (subtract dB). This is the fixture attenuation. 4.2.1.3 Reference fixture technique 4.2.1.3.1 Construct a reference
22、fixture that duplicates the specimen fixture but without the specimen. Include both near and far ends; see figure A.1.b. Connect the network analyzer ports, or the signal generator and spectrum analyzer to the appropriate locations of the driven line fixture. 4.2.1.3.2 When using a network analyzer,
23、 measure the fixture attenuation (S21). 4.2.1.3.3 When using a spectrum analyzer, measure the power from the generator through the fixture. Then divide the magnitude of this signal by that of the reference measurement performed in 4.2.1.2.3 at each frequency (subtract dB). This is the fixture attenu
24、ation. 4.2.1.4 Specimen attenuation measurement 4.2.1.4.1 Add specimen to fixture. 4.2.1.4.2 When using a network analyzer, connect the analyzer drive port to the near end of the fixture and the receiver port of the analyzer to the far end of the fixture. Measure the specimen- with-fixture attenuati
25、on in dB. 4.2.1.4.3 When using a spectrum analyzer, connect the generator output port to the near end of the fixture and the analyzer input to the far end of the fixture. Measure the signal power (typically in dBm). Divide the magnitude of this signal by that of the reference measurement, see 4.2.1.
26、1.2, at each frequency (subtract dBm). Record specimen-with-fixture results in dB. 4.2.1.5 Divide the specimen-with-fixture attenuation by the fixture attenuation (subtract dB) and plot. This is the specimen attenuation. Record single frequency results and tabulate, if requested. EIA-364-101 Page 6
27、4.2.2 Impedance analyzer (open/short method) 4.2.2.1 Calibrate the instrument according to the manufacturers instructions. This is typically done using short and open circuit standards connected one at a time at the specimen measurement location of the fixture. 4.2.2.2 Connect the specimen to the fi
28、xture with the far end of the specimen open-circuited, and measure the magnitude and phase of the specimen plus fixture impedance. 4.2.2.3 Short-circuit the far end of the specimen, and measure the magnitude and phase of the specimen plus fixture impedance. 4.2.2.4 Calculate the attenuation of the s
29、pecimen plus fixture using the following equations: 1)P = (|ZOP| |ZST|)1/2 and = (ST - OP) / 2, where: ZOP and OP are the open-circuit impedance and phase, respectively, and ZST and ST are the short-circuit impedance and phase, respectively. The attenuation constant, = 8.6859 (1/2l) ln (1+x)2 + y2)
30、/ (1-x)2 + y2)1/2 dB/m, where: l = specimen physical length (meters) x = P cos y = P sin 4.2.2.5 Divide the specimen-with-fixture attenuation by the fixture attenuation (subtract dB) and plot. This is the specimen attenuation. Record single frequency results and tabulate, if requested. 4.2.3 Additio
31、nal measurements Repeat this entire procedure for each measurement requested. 1) Procedure and equations from “Measuring Cable Parameters,” Hewlett-Packard Application Note 380-2, p.15. EIA-364-101 Page 7 4.3 Method B, time domain This method requires that the network analyzer procedure be followed,
32、 but with the following changes. A TDR in time domain transmission (TDT) mode with a triggered short impulse generator to measure the response of the specimen to an impulse stimulus shall be used. Fast fourier transform (FFT) software is used to compute the attenuation of the specimen in the frequen
33、cy domain. 4.3.1 Connect the TDR output to the input of an impulse generator. 4.3.2 Connect the output of the impulse generator to the near end of the test fixture, and connect the far end of the test fixture to the input of a TDR sampling head. 4.3.3 For each measurement, measure the TDT response t
34、o the impulse stimulus. 4.3.4 Compute the FFT of the time domain response, the result being the attenuation in the frequency domain. From these data the complex propagation constants alpha (attenuation versus frequency) and beta (phase versus frequency) may be calculated over a very wide frequency r
35、ange. If combined with low frequency capacitance measurements, the specimen may be completely characterized, including attenuation as well as complex impedance as functions of frequency. 5 Details to be specified The following details shall be specified in the referencing document: 5.1 Method to be
36、used, time or frequency domain 5.2 Specimen signal and ground assignments for each measurement. As a minimum, the driven conductor or conductor pair, the nearest signal conductors in each direction, and the associated (adjacent) grounds of all these, shall be identified. NOTE A sufficient number of
37、lines to be measured based on a consideration of geometry, should be specified so that the best and worst case performance will be determined. It is recommended that the following be considered: conductor spacing, conductor orientation, conductor length, etc. 5.3 The type of drive signal, single-end
38、ed or differential. Refer to 2.2.1 in the special case of differential and not balanced signals. 5.4 Specimen environment impedance if other than 50 ohms for single-ended or 100 ohms for differential. EIA-364-101 Page 8 5.5 Points between which the attenuation shall be measured 5.6 Measurement frequ
39、ency range 5.7 Tabulated single frequency results, if desired 5.8 Plot magnitude format, if other than dB and log frequency 5.9 Any special requirements with respect to fixture and termination construction and electrical properties. 5.10 Any special calibration technique 6 Test documentation Documen
40、tation shall contain the details specified in clause 5, with any exceptions, and the following: 6.1 Title of test 6.2 Test equipment used, and date of last and next calibration 6.3 Measured fixture, measured specimen-with-fixture, and calculated specimen attenuation plots and tabulated single freque
41、ncy results. 6.4 Balun specifications, if used 6.5 Test method used, time domain or frequency domain, (direct or open/short) 6.6 Observations 6.7 Name of operator and date of test EIA-364-101 Page A-1 Annex A Normative Figure A.1.a - Insertion technique Figure A.1.b - Reference fixture technique Fig
42、ure A.1 - Technique diagrams EIA-364-101 Page A-2 Figure A.2 Single-ended termination EIA-364-101 Page A-3 Minimum loss pad equations: R1 = Zo 1 - (100 / Zo) 0.5 / 2 R1 = 100 1 - (Zo / 100) 0.5 / 2 R2 = 100 / 1 - (100 / Zo) 0.5 R2 = Zo / 1 - (Zo / 100) 0.5Figure A.3 - Differential (balanced) termina
43、tions Figure A.4 - Example of specimen in fixture for attenuationEIA-364-101 Page B-1 B Informative B.1 Practical guidance Near perfect resistive terminations of the signal lines may not be possible at high frequencies due to parasitic reactances in both signal and ground conductors. These reactance
44、s will have an impact on measured results. In this case it is desirable that the test fixture duplicate the exact geometry (parasitics) of the actual application. This may involve the use of transmission lines in addition to the components of figures A.1 and A.2. Most instruments used for these meas
45、urements are internally terminated in 50 ohms at both source and detector ports. If in the review or use of this document, a potential change is made evident for safety, health or technical reasons, please fill in the appropriate information below and mail or FAX to: Electronic Components Industry A
46、ssociation EIA Standards & Technology Department 2214 Rock Hill Rd., Suite 170 Herndon, VA 20170 FAX: (571-323-0245) Document 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:
47、 b. Recommended Changes: c. Reason/Rationale for Recommendation: Additional Remarks: Signature: Date: FOR ECIA USE ONLY Responsible Committee: Chairman: Date comments forwarded to Committee Chairman: Electronic Components Industry Association 2214 Rock Hill Road, Suite 170 * Herndon, VA 20170 * tel 571-323-0294 * fax 571-323-0245 www.eciaonline.org
