1、.- I - EIA 545 89 m 3234600 0074bb2 9 m d , ANSJ3IA-545-1989 APPROVED: July 28, 1989 IA STANDARD Blectromechanical Switch Test Method for Electrostatic Discharge (ESD) EIA-545 SEPTEMBER 1989 ELECTRONIC INDUSTRIES ASSOCIATION ENGINEERING DEPARTMENT NOTICE EIA Engineering Standards and Publications ar
2、e designed 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. Exist
3、ence of such Standards and Publications shall not in any respect preclude any member or non-memberof EIA 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 th
4、an EIA members, whether the standard is to be used either domestically or internationally. Recommended Standards and Publications are adopted by EIA without regard to . whether or not their adoption may involve patents on articles, materials, or processes. By such action, EIA does not assume any lia
5、bility to any patent owner, nor does it assume any obligation whatever to parties adopting the Recommended Standard or Publication. This EIA Standard is considered to have international standardization implication, but the International ElectrotechnicalCommission activity has not progressed to the p
6、oint where a valid comparison between the EIA standard 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 responsibilityof the user of this Standard to establish appropriate safe
7、ty and health practices and to determine the applicability of regulatory limitations before its use. Copyright 1989 Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineering Department 2001 Eye Street, N.W. Washington, D.C. 20006 PRICE: $1 1 .O0 All rights reserved Printed in U.S.A. . EIA 545 89 m
8、3234b00 0074bb4 2 m 7 EIA-545 Electrostatic Discharge (ESD) Test Method (From Standards Proposal No. 1734-A formulated under the cognizance of the EIA P-13 Committee on Switches.) This standard contains the major technical contents of International Electromechanical Commission, recommendation 801-2,
9、 Electromagnetic compatibility for industrial - process measurement and control equipment Part 2: Electrostatic Dischage Requirements. It differs from IEC recommendation 801-2 in certain minor respects as given below. o 1. Level 4 test voltage increased to 16 kV from 15 kv. 2. Test procedure II adde
10、d. 3. Restricted to cover testing of discrete switches only. / i P EIA 545 89 m 3234600 0074665 4 m EIA-545 Page 1 ELECTROSTATIC DISCHARGE (ESD) TEST METHOD l. PURPOSE This test is performed to determine the level at which electrostatic discharge occurs through or around a manually operated electrom
11、echanical switch, which is not equipped with a ground plane circuit protection feature. It is intended to be used on switches which have been fabricated using normal manufacturing workmanship standard for cleanliness. This test method may not be appropriate for switch application in areas other than
12、 normal office environments. 2. SEVERITY LEVELS The following severity levels are recommended for the ESD-test: LEVEL TEST VOLTAGE (+/- 10%) 1 2 3 2 kV 4 kV 8 kV O 4 16 kV NOTE 1: Details concerning the various parameters which may influence the-voltage level-to which the the human body may be charg
13、ed are given in Appendix II. This Appendix also contains examples of the application of the severity levels related to environmental (installation) classes. 3. APPARATUS The ESD simulator used may be of varied construction. Appendix I to this test procedure shows one possible construction. In order
14、to make it possible to compare test results obtained from different test simulators, the following characteristics shall be verified: 3.1 Risetime of the discharge current: 5 ns +/- 30% at 4 kV Duration of the discharge current: 30 ns +/- 30% at 4 kV Peak value of the discharge current: +/- 30% 9 A
15、at 2 kV 18 A at 4 kV 37 A at 8 kV 74 A at 16 kV NOTE: Measuring instrument bandwidth 100 MHz. EIA 545 89 m 3234600 0874bbb b m EIA-545 Page 2 3.2 The discharge of the ESD simulator shall be applied to a 2 ohm or less resistive load. The discharge electrode shall be advanced to the load until the dis
16、charge occurs. The discharge circuit including the ground connection shall be as short as possible. 3.3 The load shall be a set of at least five non-inductive resistors (carbon type, minimum 1 W power rating, 10 ohms or less) connected in parallel forming a circular array. The set of resistors shall
17、 be coaxial with the resistor for matching the impedance of the measuring circuit. The recommended constructional arrangement of the resistive load for verifying the ESD simulator characteristics is given in Figure 2. 3.4 The typical waveform of output current of the simulator for the verification p
18、rocedure is given in Figure 3. 4. TEST SAMPLE MOUNTING 4.1 The switch to be tested shall be mounted in the center of a test plate 300 mm (11.8 inches) square in a manner to simulate the intended application. 4.2 For switches intended for printed circuit board (PCB) termination, Figure 4 shows the mo
19、unting method to be used to the ground plane. If the switch is intended to be PCB mounted with a surrounding metal subpanel or front panel, a metal panel extending 10 mm (0.40 inch) on all sides of the switch is mounted to the switch in the intended manner. If the panel is plastic or if there is no
20、panel adjacent to the switch, this is omitted from the test specimen. 4.3 For switches with terminals for wires, the mounting method to the ground plane is shown in Figure 5. If the construction of the switch prevents contact of the electrical terminals with the ground plane (recessed terminals), wi
21、res must be used to connect the terminals to the ground plane. If the switch is intended to be mounted to or adjacent to a metal subpanel or front panel, a metal panel extending 10 mm (0.40 inch) on all sides of the switch is mounted to the switch in the intended manner. If the panel is plastic or i
22、f no panel is used, this is omitted from the test specimen. If a clamping device is needed to hold the switch in place, it must be of insulating material and must not cover or change the minimum spacing of any metal switch parts to the ground plane or to the switch actuator. a “ - “_ EIA 545 B9 m 32
23、34b00 0074bb7 B m EIA-545 Page 3 5. TEST SET-UP 5.1 The test specimen prepared according to paragraph 4 above should be located on a flat surface at least 1 meter (3.3 feet) from any surrounding objects, including test laboratory walls. The test equipment should be arranged so that the test probe of
24、 the ESD simulator approaches the switch operating surface perpendicular to that surface. 5.2 The ground cable of the ESB simulator shall be.2 meters (6.5 feet) in length and shall be connected to the ground reference plane. The ground reference plane in turn is connected to common ground as shown i
25、n Figures 4 and 5. All grounding connections must be of low impedance, using clamping devices or soldered connections. 5.3 7:mbient conditions in the vicinity sf the test shall be within the following limits: Ambient temperature 15 to 35 degrees C Relative humidity 45 to 75% Atmospheric pressure 68
26、kPa (680 mbar) to 106 kPa (1060 mbar) NOTE: Any other value may be agreed upon by manufacturer, user and independent laboratory. 5.4 The electromagnetic environment of the test area shall not be sufficient to influence the test results. 6. TEST PROCEDURE 6.1 Procedure I Isolation Material Breakdown
27、6.1.1 The test procedure is intended to find the lowest voltage at which an operators finger or other switch operating device will discharge to ground when contacting the switch being tested. The test is conducted by applying the single discharges at a preselected test point (the one that gives the
28、lower breakdown voltage). The test point shall be selected by exploring the entire actuator surface, including the periphery and areas adjacent to any opening in the actuating surface, with the ESD simulator probe operating in a repetitive mode of up to 20 discharges per second. By operating in this
29、 manner and gradually increasing the ESD simulator output voltage, the area of interest can be located quickly and then tested in the single discharge mode. The exact test point may be specified in the detail specification. EIA-545 - . Page 4 EIA 545 89 3234600 007L)bbA T W 6.1.2 The test data shall
30、 be taken using single discharges of the ESD simulator applied at the pre-selected point in the following manner: 6.1.2.1 The ESD simulator probe is located vertically to the operating surface, just contacting the surface at the selected test point. 6.1.2.2 The output voltage is set at a point just
31、below the level where breakdown is expected to occur. Minimum steps of the voltage should be no greater than 200 volts. 6.1.2.3 The voltage is applied; if breakdown odcurs the voltage is reset to a slightly lower value; if breakdown does not occur the voltage is set at a slightly higher value. Minim
32、um steps of the voltage should be no greater than 200 volts. 6.1.2.4 After each discharge, the ESD simulator probe must be removed from contact with the test sample. The time interval between successive discharges must be at least 1 second. 6.1.2.5 A new test specimen shall be used after each breakd
33、own has occurred to avoid the effects of a carbon track on the plastic surface under test. 6.2 Procedure II Discharge Effect at Specified Voltages 6.2.1 This test procedure is intended to verify the capability to withstand specified voltage discharges or to evaluate the effects of specified voltage
34、discharges. 6.2.2 The test shall be performed by applying the ESD simulator probe in the specified test area and applying the test voltage or series of voltages as specified in the detail specification. If no details are specified, the te.st voltage shall be applied 2 times to each ungrounded electr
35、ical terminal and 2 times to each ungrounded major surface of the specimen. 6.3 Test Report fo,r Procedures I or II The test report must contain the following information: 6.3.1 Test conditions including ambient temperature, relative humidity and atmospheric pressure at the time of the test. 6.3.2 T
36、he mounting procedure used and the parts of the specimen electrically grounded. EIA 545 89 I 3234600 0074667 L I EIA-545 Page 5 7. e 8. O 6.3.3 6.3.4 6.3.5 6.3.6 6.3.7 The procedure used and the details of voltage application. The point on the surface where breakdown occurred (Procedure I) or the po
37、int of application of discharges (Procedure II). The minimum breakdown voltage (Procedure I) or the voltage or voltages applied (Procedure II). Any special phenomenon or physical damage observed. The results of electrical or mechanical tests specified in the detail specification. DEFINITIONS Electro
38、static Discharge (ESD).: The transfer of an electrostatic charge between bodies of different electrostatic potential. Energy Storage Capacitor: The capacitor of the ESD simulator representing the capacity of a human body charged to the test voltage level. Holding Time: Interval of time within which
39、the decrease of the output voltage, due to leakage prior to discharge, is not greater than 10%. SUMMARY The following must be specified in the. product detail specification: 8.1 Test voltage level (paragraph 2) . 8.2 Method of mounting and points or terminals to be grounded (paragraph 4) . 8.3 Test
40、Procedure (I or II paragraph 6) . 8.4 Points of voltage application or specimen (paragraph 6.2.2). 8.5 Number of discharges and sequence of application (paragraph 6.2.2. ) . 8.6 Physical or mechanical requirements or observations to be made (paragraph 6.3.6). 8.7 Functional or electrical tests befor
41、e and after discharges (paragraph 6.3.7). EIA 545 89 m 3234b00 0074b70 B m EIA-545 Page 6 APPENDIX I ESD testers are available in the commercial market or can be designed and constructed by the user. The following is the description of one piece of such equipment. 1, The tester in its simpler form c
42、onsists of a charging resistor, an energy storage capacitor, a discharge resistor and a power supply unit. A simplified diagram of the ESD simulator is given in Figure 1. The waveform of the pulse which is generated while the static electricity discharge takes place, is not formed in the simulator p
43、rior to the discharge. The waveform depends on the type of load. 2. Characteristics and performance of the ESD simulator. Discharge electrode pF. Common Ground A Figure 1: Simplified diagran of the ESD airnulator EIA-545 Page 7 The characteristics of the ESD simulator are: Energy Storage Capacitor (
44、Cs) 150 pF +/- 10% Discharge Resistor (Rd) 150 ohms +/- 5% Charging Resistor (Rch) 100 megohms +/- 10% Output Voltage Trigger Switch 2.0-16.5 kV (measured at the discharge energy storage capacitor) Bounce free, mercury wetted or equivalent Polarity of the output voltage Positive Holding time 5 secon
45、ds Discharge, mode of operation Single discharge (time between successive discharges at least 1 S but simulator should be able to generate 20 discharges per second for exploratory purposes only Risetime of the discharge current at 4 kV 5 ns +/- 30% Pulse duration of the discharge current when above
46、50% amplitude at 4 kv 30 ns +/- 30% Peak value of the discharge current +/- 30% 9 A at 2 kV 18 A at 4 kv 37 A at a kv 74 A at 16- kV The energy storage capacitor and the discharge resistor must be placed as closely as possible to the discharge electrode. The grounding cable of the test simulator sha
47、ll be an insulated copper flexible strap, with the following dimensions: Length Width Thickness 2000 mm (approx.) 20 mm (approx.) 0.1 mm (approx.) O A standard flat cable of the width specified above (with all the conductors connected in parallel) may be used instead of the copper strap. If round co
48、nductors are used, the minimum conductor size shall be 22 AWG (abou-t 0.7 mm diameter). EIA S45 89 m 3234600 0074672 L m , EIA-545 Page 8 50 na (1.97 in.) tor Resistors in CirCUlarV friction between the operators clothing and the chair can also produce an exchange of charges. An operators body may b
49、e charged either directly or by electrostatic induction; in the latter case a conducting carpet will give no protection unless the operator is adequately grounded to it. chart of Figure 6 shows the voltage which different fabrics acquire as a function o humidity. Equipment may be directly subjected to discharges from operators charged to these values. Equipment may also be subjected to electromagnetic energies whenever discharges occur between metal objects, e.g. chairs and tables,-in the proximity of the equipment. The effect of the operator discharge may be a temporary int
