1、 EIA STANDARD TP-69A Low Level Induction Measurement for Electrical Contacts of Electrical Connectors EIA-364-69A (Revision of EIA-364-69) March 2002 ANSI/EIA-364-69A-2002(R2015) Approved: March 6, 2002 Reaffirmed: March 27, 2015 EIA-364-69ANOTICE EIA Engineering Standards and Publications are desig
2、ned 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 of
3、 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 ECI
4、A 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 it
5、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 progresses to the point where a valid comparison between the EIA Stand
6、ard 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 appli
7、cability of regulatory limitations before its use. (From Standards Proposal No. 4830, formulated under the cognizance of the CE-2.0 Committee on EIA National Connector and Socket Standards, and reaffirmed per Standards Proposal No. 5346.05). Published by Electronic Components Industry Association 20
8、15 Standards resolution: 0.1 nH; test frequency range: appropriate for the value of inductance being measured. See figure 1 for recommended test frequency plot. test frequency accuracy: 0.1%. EIA-364-69A Page 2 Figure 1 - Recommended test frequency range plot as a function of specimen inductance NOT
9、E Check the equipment manufacturers application notes or operating manuals for information regarding the minimum reactance required in the test specimen to optimize measurement accuracy at the desired measurement frequency(s). 2.2 Fixture The test fixture shall be a mechanically stable assembly. The
10、 spacing between test points should be adjustable to accept the specimen without the use of additional conductors. In general, the conductors of the test fixture should be perpendicular to the test sample as shown in figure A.1. NOTES 1 One-piece connectors require the use of a special fixture to al
11、low connection to the measuring equipment. This fixture shall have a known inductance if it cannot be zeroed out with the reference rod. 2 It is recommended that the fixtures provided by the equipment manufacturer be used as they typically improve measurement accuracy. Recommendedmeasurement areaEIA
12、-364-69A Page 3 3 Test specimen 3.1 Description The test specimen shall consist of one of the following: an individual contact; a mated contact assembly that would normally be installed in a connector; one-piece connectors (e.g. card edge connectors or chip sockets); mated two-piece connectors. 4 Te
13、st procedure Unless otherwise specified in the referencing document, the test frequency(s) should be in the recommended area shown in figure 1. The plot identifies the minimum frequency to ensure the minimum 5 ohms inductive reactance required to minimize measurement error using typical 50 ohm measu
14、rement equipment. The test professional should be aware of the limitations and associated accuracy levels when measuring values below 20 nanohenrys. Place the specimen a minimum of 5 cm from any objects that would affect measured results. 4.1 The inductance of at least three specimens shall be measu
15、red unless otherwise specified in the referencing document. In the case of multi-contact connectors, at least three specimens of each type of contact from at least three connector specimens shall be measured unless otherwise specified in the referencing document. For pin and socket contacts the dept
16、h of engagement shall be the nominally designed engagement depth unless specified in the referencing document. 4.2 The point of measurement shall be between the termination points of the specimen as shown in figure A.1. 4.3 Adjust the spacing of the test fixture test points to accept the specimen. 4
17、.4 Remove the specimen from the fixture, and in its place insert a round rod of known diameter having a length equal to that of the test sample. The rod diameter should be chosen to yield a calculated value slightly lower than that expected for the specimen. 4.4.1 The reference rod shall remain stra
18、ight at all times. The calculation of inductance for the reference rod is based on a straight conductor. EIA-364-69A Page 4 4.4.2 When measuring a 90 degree specimen as shown in Figure A.1.C, the straight reference rod is to be installed diagonally on the test fixture, contacting the test fixture at
19、 the same points that the test sample will contact when it is installed in place of the rod. NOTE The test requestor should be aware that the value obtained from a 90 degree specimen (or any non collinear specimen) may not be accurate due to coupling with the fixture conductors. 4.5 Use the formula
20、given in annex A to calculate the self inductance of the reference rod. 4.6 Set the test equipment to the desired measurement frequency. 4.7 Zero the RLC meter or inductance meter with the instrument set for a resolution of 0.1 nH. 4.8 Remove the reference rod and replace it with the test specimen w
21、ithout disturbing the position of the test fixture conductors or the settings of the RLC meter. 4.9 Record the value indicated by the RLC meter. The inductance of the test specimen is the sum of this value plus the inductance of the reference rod determined in 4.5. NOTE when special fixtures are use
22、d (as in the case of one-piece connectors) the inductance of the special fixture shall be subtracted from the result of the sum in 4.8 to determine the actual self inductance of the specimen. 4.10 The test can be verified by the measurement of a second reference rod having a value equal to or slight
23、ly higher than the final value computed for the test sample. 5 Details to be specified The following details shall be specified in the referencing document: 5.1 Specimen description and measurement points 5.2 Depth of engagement for pin and socket contacts if other than nominally designed engagement
24、 depth. 5.3 Test frequency(s) to be used 5.4 Special fixture requirements if any 5.5 Output format (e.g. Inductance versus frequency plots or tabular listing of data) 5.6 Quantity of specimens (and/or contacts within the specimen) to be measured EIA-364-69A Page 5 6 Test documentation Documentation
25、shall contain the details specified in clause 5, with any exceptions, and the following: 6.1 Title of test 6.3 Test equipment used, and date of last and next calibration 6.4 Method of mounting test specimen to test fixture 6.5 Ambient temperature and humidity 6.6 Measured values and test frequency(s
26、), for both the specimen and reference rod. 6.7 Name of operator and date of test EIA-364-69A Page A-1 Annex A Test fixture (normative) A.1 Test fixture conductors Figure A.1 Test fixture conductors Figure A.1.A Straight pin and socket Figure A.1.B Straight printed circuit pin and standard socket Fi
27、gure A.1.C 90 printed circuit socket and standard pin Test fixture Reference rod EIA-364-69A Page A-2 A.2 Self inductance A.2.1 Rod The test method is based on the following formula: 1) ()+= 12/4log303.28.510G22G22G22 ddL where: L = self inductance in nanohenrys = length in inches d = diameter in in
28、ches = permeability = correction factor for skin effect versus frequency; see nomograph figure A.2 Correction factor for skin effect () Figure A.2 Skin effect versus frequency nomograph 1) F.E. Terman, Radio Engineers Handbook, McGraw-Hill, New York, 1943, pages 48 and 49. EIA-364-69A Page A-3 A.2.2
29、 Rectangular bar The calculation of the self inductance of a straight rectangular bar is given in footnote 2), page 51. 2) F. W. Grover, Inductance Calculations Working Formulas and Tables, van Nostrand, 1946. Reprinted by Instrument Society of America, 1980, pages 35 and 261. EIA-364-69A Page B-1 B
30、 Guidance to determine the self inductance (informative) B.1 The accuracy of inductance measurements below 100 nH is severely limited by the residual inductance of fixturing conductors used to connect the specimen to the test equipment. The conventional technique of using a short copper strip to “ze
31、ro” an inductance or RLC meter can result in an error of 50% or more. B.2 Residual errors in the instrument used and any changes in the test fixture configuration during the test can significantly affect the measurement results. Uncertainties are minimized by the use of the reference rod. B.3 Care s
32、hall be taken in interpreting the measured self inductance of an isolated contact compared to the same contact when it is used in close proximity to other conductors (e.g. ground planes or other contacts). Any conductors or ferro-magnetic materials in close proximity to the measured contact may intr
33、oduce error in the measured self inductance. ECIA Document Improvement Proposal 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 As
34、sociation EIA Standards & Technology Department 2214 Rock Hill Rd., Suite 265 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:
35、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 265 * Herndon, VA 20170 * tel 571-323-0294 * fax 571-323-0245 www.ecianow.org
