IEC 60749-37 pdf download – Semiconductor devices – Mechanical and climatic test methods – Part 37: Board level drop test method using an accelerometer

IEC 60749-37 pdf download – Semiconductor devices – Mechanical and climatic test methods – Part 37: Board level drop test method using an accelerometer
1scope and object
This part of lEC 60749 provides a test method that is intended to evaluate and compare dropperformance of surface mount electronic components for handheld electronic productapplications in an accelerated test environment,where excessive flexure of a circuit boardcauses product failure.The purpose is to standardize the test board and test methodology toprovide a reproducible assessment of the drop test performance of surface-mountedcomponents while producing the same failure modes normally observed during product leveltest.
The purpose of this standard is to prescribe a standardized test method and reportingprocedure.This is not a component qualification test and is not meant to replace any systemlevel drop test that may be needed to qualify a specific handheld electronic product. Thestandard is not meant to cover the drop test required to simulate shipping and handling-related shock of electronic components or PCB assemblies. These requirements are alreadyaddressed in test methods such as lEC 60749-10.The method is applicable to both areaarray and perimeter-leaded surface mounted packages.
This test method uses an accelerometer to measure the mechanical shock duration andmagnitude applied which is proportional to the stress on a given component mounted on astandard board.The test method described in the future lEc 60749-401 uses strain gauge tomeasure the strain and strain rate of a board in the vicinity of a component.The detailedspecification states which test method is to be used.
2Normative 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 editionof the referenced document (including any amendments) applies.
IEC 60749-10:2002,Semiconductor 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 solderingheat
IEC 60749-20-1，Semiconductor devices – Mechanical and climatic test methods – Part 20-1:Handling，packing，labelling and shipping of surface-mount devices sensitive to the combinedeffect of moisture and soldering heat2
3 Terms and definitions
For purposes of this document, the following terms and definitions apply.
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 theboard
3.4
handheld electronic product
product that can conveniently be stored in a pocket(of sufficient size) and used when held inuser’s hand
NOTE Handheld electronic products include cameras,calculators,cell phones，pagers,palm-size PCs (formerlycalled ‘pocket organizers’)， personal computer memory card international association (PCMCIA) cards，smartcards, 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 between the instant when the acceleration first reaches 10 % of its specifiedpeak level and the instant when the acceleration first returns to 10 % of the specified peaklevel after having reached that peak level
3.7
table drop height
free-fall drop height of the drop table needed to attain the prescribed peak acceleration andpulse duration
3.8
event
electrical discontinuity of resistance greater than 1 000 Q lasting for 1 us or longer
3.9
event detector
continuity test instrument capable of detecting electrical discontinuity of resistance greaterthan 1 0o0 o lasting for 1 us or longer
4Test apparatus and components
4.1 Test apparatus
The shock-testing apparatus shall be capable of providing shock pulses up to a peakacceleration of 2 900 m-s-2 with a pulse duration between 0,3 ms and 8,0 ms to the body ofthe device and a velocity change of 710 mm·s-1 to 5 430 mm’-s-1.
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 packages (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 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.