1、BRITISH STANDARDBS EN 60749-37:2008Semiconductor devices Mechanical and climatic test methods Part 37: Board level drop test method using an accelerometer ICS 31.080.01g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g
2、53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 60749-37:2008This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 May 2008 BSI 2008ISBN 978 0 580 55509 1National forewordThis British Standard is the UK implementation o
3、f EN 60749-37:2008. It is identical to IEC 60749-37:2008. It supersedes DD IEC/PAS 62050:2004 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee EPL/47, Semiconductors.A list of organizations represented on this committee can be obtained on request to its
4、 secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corrigenda issued since publicationDate CommentsEUROPEAN S
5、TANDARD EN 60749-37 NORME EUROPENNE EUROPISCHE NORM April 2008 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2008 CENELEC - Al
6、l rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60749-37:2008 E ICS 31.080.01 English version Semiconductor devices - Mechanical and climatic test methods - Part 37: Board level drop test method using an accelerometer (IEC 60749-37:2008) Disp
7、ositifs semiconducteurs - Mthodes dessais mcaniques et climatiques - Partie 37: Mthode dessai de chute au niveau de la carte avec utilisation dun acclromtre (CEI 60749-37:2008) Halbleiterbauelemente - Mechanische und klimatische Prfverfahren - Teil 37: Prfverfahren Fall der Leiterplatte unter Verwen
8、dung eines Beschleunigungs-Messgertes (IEC 60749-37:2008) This European Standard was approved by CENELEC on 2008-03-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard wit
9、hout any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other langu
10、age made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Den
11、mark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Foreword The text of document 47/1937/FDIS, future editi
12、on 1 of IEC 60749-37, prepared by IEC TC 47, Semiconductor devices, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60749-37 on 2008-03-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identi
13、cal national standard or by endorsement (dop) 2008-12-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2011-03-01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 60749-37:2008 was approved by CENELEC
14、 as a European Standard without any modification. _ BS EN 60749-37:2008 2 CONTENTS INTRODUCTION.4 1 Scope and object5 2 Normative references .5 3 Terms and definitions .5 4 Test apparatus and components.6 4.1 Test apparatus 6 4.2 Test components.7 4.3 Test board.7 4.4 Test board assembly .7 4.5 Numb
15、er of components and sample size .8 5 Test procedure .8 5.1 Test equipment and parameters 8 5.2 Pre-test characterization .9 5.3 Drop testing.11 6 Failure criteria and failure analysis .11 7 Summary13 Annex A (informative) Preferred board construction, material, design and layout .14 Bibliography18
16、Figure 1 Typical drop test apparatus and mounting scheme for PCB assembly 9 Figure 2 Typical shock test half-sine pulse graphic and formulae .10 Figure 3 Fundamental mode of vibration of PCB supported with four screws13 Figure A.1 Recommended test board size and layout.17 Table 1 Quantity of test bo
17、ards and components required for testing .8 Table 2 Component locations for test boards .12 Table A.1 Test board stack-up and material .14 Table A.2 Mechanical property requirements for dielectric materials 15 Table A.3 Recommended test board pad sizes and solder mask openings .16 Table A.4 X, Y loc
18、ations for components centre 17 BS EN 60749-37:2008 3 Annex ZA (normative) Normative references to international publications with theircorresponding European publications19INTRODUCTION Handheld electronic products fit into the consumer and portable market segments. Included in handheld electronic p
19、roducts are cameras, calculators, cell phones, cordless phones, pagers, palm size PCs, personal computer memory card international association (PCMCIA) cards, smart cards, personal digital assistants (PDAs) and other electronic products that can be conveniently stored in a pocket and used while held
20、 in users hand. These handheld electronic products are more prone to being dropped during their useful service life because of their size and weight. This dropping event can not only cause mechanical failures in the housing of the device but also create electrical failures in the printed circuit boa
21、rd (PCB) assemblies mounted inside the housing due to transfer of energy through PCB supports. The electrical failures may result from various failure modes such as cracking of the circuit board, track cracking on the board, cracking of solder interconnections between the components and the board, a
22、nd component cracks. The primary driver of these failures is excessive flexing of the circuit board due to input acceleration to the board created from dropping the handheld electronic product. This flexing of the board causes relative motion between the board and the components mounted on it, resul
23、ting in component, interconnect or board failures. The failure is a function of the combination of the board design, construction, material, thickness and surface finish; interconnect material and standoff height and component size. Correlation between test and field conditions is not yet fully esta
24、blished. Consequently, the test procedure is presently more appropriate for relative component performance than for use as a pass/fail criterion. Rather, results should be used to augment existing data or establish a baseline for potential investigative efforts in package/board technologies. The com
25、parability between different test sites, data acquisition methods, and board manufacturers has not been fully demonstrated by existing data. As a result, if the data are to be used for direct comparison of component performance, matching studies must first be performed to prove that the data are in
26、fact comparable across different test sites and test conditions. This method is not intended to substitute for full characterization testing, which might incorporate substantially larger sample sizes and increased number of drops. Due to limited sample size and number of drops specified here, it is
27、possible that enough failure data may not be generated in every case to perform full statistical analysis. BS EN 60749-37:2008 4 SEMICONDUCTOR DEVICES MECHANICAL AND CLIMATIC TEST METHODS Part 37: Board level drop test method using an accelerometer 1 Scope and object This part of IEC 60749 provides
28、a test method that is intended to evaluate and compare drop performance of surface mount electronic components for handheld electronic product applications in an accelerated test environment, where excessive flexure of a circuit board causes product failure. The purpose is to standardize the test bo
29、ard and test methodology to provide a reproducible assessment of the drop test performance of surface-mounted components while producing the same failure modes normally observed during product level test. The purpose of this standard is to prescribe a standardized test method and reporting procedure
30、. This is not a component qualification test and is not meant to replace any system level drop test that may be needed to qualify a specific handheld electronic product. The standard is not meant to cover the drop test required to simulate shipping and handling-related shock of electronic components
31、 or PCB assemblies. These requirements are already addressed in test methods such as IEC 60749-10. The method is applicable to both area array and perimeter-leaded surface mounted packages. This test method uses an accelerometer to measure the mechanical shock duration and magnitude applied which is
32、 proportional to the stress on a given component mounted on a standard board. The test method described in the future IEC 60749-401uses strain gauge to measure the strain and strain rate of a board in the vicinity of a component. The detailed specification states which test method is to be used. 2 N
33、ormative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60749-10:2002, Semiconduc
34、tor devices Mechanical and climatic test methods Part 10: Mechanical shock IEC 60749-20, Semiconductor devices Mechanical and climatic test methods Part 20: Resistance of plastic-encapsulated SMDs to the combined effect of moisture and soldering heat IEC 60749-20-1, Semiconductor devices Mechanical
35、and climatic test methods Part 20-1: Handling, packing, labelling and shipping of surface-mount devices sensitive to the combined effect of moisture and soldering heat23 Terms and definitions For purposes of this document, the following terms and definitions apply. 1Under consideration. 2In preparat
36、ion. BS EN 60749-37:2008 5 3.1 component packaged semiconductor device 3.2 single-sided PCB assembly printed circuit board assembly with components mounted on only one side of the board 3.3 double-sided PCB assembly printed circuit board assembly with components mounted on top and bottom sides of th
37、e board 3.4 handheld electronic product product that can conveniently be stored in a pocket (of sufficient size) and used when held in users hand NOTE Handheld electronic products include cameras, calculators, cell phones, pagers, palm-size PCs (formerly called pocket organizers), personal computer
38、memory card international association (PCMCIA) cards, smart cards, mobile phones, personal digital assistants (PDAs) and other communication devices. 3.5 peak acceleration maximum acceleration during the dynamic motion of the test apparatus 3.6 pulse duration acceleration interval time interval betw
39、een the instant when the acceleration first reaches 10 % of its specified peak level and the instant when the acceleration first returns to 10 % of the specified peak level after having reached that peak level 3.7 table drop height free-fall drop height of the drop table needed to attain the prescri
40、bed peak acceleration and pulse duration 3.8 event electrical discontinuity of resistance greater than 1 000 lasting for 1 s or longer 3.9 event detector continuity test instrument capable of detecting electrical discontinuity of resistance greater than 1 000 lasting for 1 s or longer 4 Test apparat
41、us and components 4.1 Test apparatus The shock-testing apparatus shall be capable of providing shock pulses up to a peak acceleration of 2 900 ms2with a pulse duration between 0,3 ms and 8,0 ms to the body of the device and a velocity change of 710 mms1to 5 430 mms1. The acceleration pulse shall be
42、a half-sine waveform with an allowable deviation from specified acceleration level not greater than 20 % of the specified peak acceleration. This is determined by a transducer having a natural frequency 5 times the frequency of the shock pulse being established and measured through a low pass filter
43、 having a band width BS EN 60749-37:2008 6 preferably at least 5 times the frequency of the shock pulse being established. It is very important that the transducer resonance does not approach the measured value. Filtering should not be used in lieu of good measurement set-up and procedure practices.
44、 The pulse duration shall be measured between the points at 10 % of the peak acceleration during rise time and 10 % of the peak acceleration during decay time. Absolute tolerances of the pulse duration shall be 30 % of the specified duration. It is recommended that the test velocity change should be
45、 10 % of the specified level. 4.2 Test components This standard covers all area arrays and perimeter-leaded surface-mountable packaged semiconductor devices such as ball grid arrays (BGA), land grid arrays (LGA), chip scale packages (CSP), thin small outline packages (TSOP) and quad flat no-lead pac
46、kages (QFN) typically used in handheld electronic product. All components used for this testing must be daisy-chained. The daisy chain should either be made at the die level or by providing daisy chain links at the lead-frame or substrate level. In case of non-daisy chain die, a mechanical dummy die
47、 shall be used inside the package to simulate the actual structure of the package. The die size and thickness should be similar to the functional die size to be used in application. The component materials, dimensions and assembly processes shall be representative of typical production device. 4.3 T
48、est board Since the drop test performance is a function of the test board used for evaluation, this standard describes a preferred test board construction, dimensions, and material that is representative of those used in handheld electronic products. If another board construction/material better rep
49、resents a specific application, the test board construction, dimensions and material should be documented. The test data generated using such a board shall be correlated at least once by generating the same data on the same component using the preferred board defined in this document (see Annex A for recommendations). 4.4 Test board assembly Prior to board assembly, all devices shall be inspected for missing balls or bent leads. Board thickness, warpage and pad sizes sha
