ASTM_F_1812_-_15.pdf

Designation:F181215Standard Test Method forDetermining the Effect of an ESD Discharge on a MembraneSwitch or Printed Electronic Device1This standard is issued under the fixed designation F1812;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method is used to determine the electrostaticdischarge(ESD)shielding effectiveness of a membrane switchassembly or printed electronic device.This test method may beused to test a membrane switch or printed electronic device todestruction,that is,to determine its maximum ESD shieldingeffectiveness,or it may be used to test the ability of amembrane switch or printed electronic device to withstand apredetermined level of exposure.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Terminology2.1 Definitions:2.1.1 discharge pulse countnumber of applied discharges.2.1.2 discharge pulse intervaltime duration between ap-plied voltage.2.1.3 ESD(electrostatic discharge)eventdetection of ap-plied charge at input/output(I/O)points.2.1.4 I/O pointsspecified conductive area,location,orcircuitry,typically all circuit paths,traces and wires.3.Significance and Use3.1 Nearly all electronic devices are susceptible to possibledamage or degradation from ESD encountered in their operat-ing environments.The sensitivity of the equipment,the poten-tial consequences of a malfunction,and the expected environ-mental conditions all impact the level of ESD protectionneeded.3.2 ESD shielding effectiveness test may be destructive,andunits that have been tested should be considered unreliable forfuture use.4.Interferences4.1 The following parameters may affect the results of thistest:4.1.1 Temperature may affect the tendency of an ESD eventto occur,4.1.2 Relative humidity may affect the tendency of an ESDevent to occur,4.1.3 Barometric pressure may affect the tendency of anESD event to occur,and4.1.4 The composition of the work bench may influence thetest results.5.Apparatus5.1 Discharge Probe.5.2 ESD SimulatorCommercially available device for ap-plying required or specified voltages,monitoring for ESDevent and selecting various voltage levels,and probes forcontact or air discharge.6.Procedure:Direct Application of Discharge6.1 Pretest Setup:6.1.1 Place switch on a nonconductive surface,or as speci-fied.6.1.2 If applicable,connect the ESD shield,ground trace,orground plane to earth ground.6.1.3 Connect all circuitry pin inputs or outputs to the ESDgenerating devices ground.6.1.4 Ambient laboratory conditions to be within:6.1.4.1 Relative humidity 30 to 60%,6.1.4.2 Temperature 15 to 35C,and6.1.4.3 Atmospheric pressure 680 to 1060 mbar or other-wise specified.6.2 In Process:6.2.1 Accumulation of charge on the membrane switch orprinted electronic device must be dissipated between succes-sive tests.6.2.2 Set the initial voltage level to 2Kv.Set discharge pulseinterval as specified.1This test method is under the jurisdiction of ASTM Committee F01 onElectronics and is the direct responsibility of Subcommittee F01.18 on PrintedElectronics.Current edition approved June 1,2015.Published July 2015.Originally approvedin 1997.Last previous edition approved in 2009 as F1812-09.DOI:10.1520/F1812-15.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.2.3 Place discharge tip perpendicular,and in contact,withswitch surface at the specified point.6.2.4 Trigger the ESD discharge and monitor.6.2.5 Check the ESD discharge event to I/O points.6.2.6 If no ESD event occurs,discharge accumulated volt-age on surface to earth ground.6.2.7 Reset and increase test voltage to next level inaccordance with Table 1(or as specified).Repeat 6.2.3 6.3.6.3 If ESD discharge event is noted,report and terminatetest.6.4 Repeat 6.2.1 6.3 for other test points.7.Procedure:Air Gap Discharge7.1 Pretest Setup:7.1.1 Position switch on a nonconductive surface,or asspecified.7.1.2 If applicable,connect the ESD shield,ground trace,orground plane to earth ground.7.1.3 Connect all circuitry pin in or outputs to the ESDgenerating devices ground.7.1.4 Ambient laboratory conditions to be within:7.1.4.1 Relative humidity to be between 30 to 60%,7.1.4.2 Temperature 15 to 35C,and7.1.4.3 Atmospheric Pressure 680 to 1060 mbar or other-wise specified.7.2 In Process:7.2.1 Set the initial voltage level to 2Kv.Set discharge pulseinterval as specified.7.2.2 Place contact air discharge tip 2 in.(50