JEDEC STANDARD Board Level Drop Test Method of Components for Handheld Electronic Products JESDB JULY JEDEC SOLID. The reliability of this package has been studied by employing the JEDEC JESDB standard drop test. In this paper, the JEDEC B-condition is applied to. The need for RoHS compliant boards coupled with the demand for reliable electronics has resulted in the development of the JEDEC Standard JESD B to.
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Depending on the monitoring system used, the failure is defined as follows: All cables shall be cleared from the drop path. The selection of packages should cover different locations on the board.
This is the applied shock pulse to the jdsd22 plate and shall be measured by accelerometer mounted at the center of base plate or close to the support posts for the board. Jesf22 thickness, warpage, and pad sizes shall also be measured using uesd22 sampling plan.
This test method is not meant to address the drop test methods required to simulate shipping and handling related shock of electronic subassemblies. Means shall be provided in the apparatus such as automatic braking mechanism to eliminate bounce and to prevent multiple shocks to the board. Experiments with different strike surface may be needed to achieve the desired peak value and duration.
Location U8 5-component configurations: A trace width of microns shall be used for all traces outside of component region.
This is pictorially shown in Figure 3.
BOARD LEVEL DROP TEST METHOD OF COMPONENTS FOR HANDHELD ELECTRONIC PRODUCTS | JEDEC
Both accelerometer and stain gage shall be connected to data acquisition system capable of measuring at a scan frequency of 20 kHz and greater with a 16 bit signal width. The PCB assembly shall be mounted to the base plate standoffs using 4 screws, one at each corner of the board. Depending on the number of components mounted per board, Table 5 shall be used to determine the minimum quantity of assembled board required for testing and total number of components to be tested.
Depending on number of components per board, Table 5 shall be used to determine the number of boards to be tested per component type. Adjustments in drop height or replacement of strike surface may be needed if the pulse deviates from the specified. Since the drop performance is a function of component location on the board, testing with components mounted on all 15 locations will provide useful information to the users of this data OEMs in proper layout of their product board.
In addition, a rectangular rosette strain gage shall be mounted on this set-up board underneath position U8 on the other side non-component side of the board to characterize strains in x and y directions as well as the principal strain and principal strain angle.
Table 1 provides the thickness, copper coverage, and the material for each layer.
JESDB B Board level drop test menthod of components for handheld eletronic products_百度文库
The maximum acceleration during the dynamic motion of the test apparatus. It should be noted that the peak acceleration and the pulse duration is a function of not only the drop height but also the strike surface. Organizations may obtain permission to reproduce a limited number of copies through entering into a license agreement. Figure 3 shows the typical drop test apparatus where the drop table travels down on guide rods and strikes the rigid fixture. This is not a component qualification test and is not meant to replace any system level drop test that maybe needed to qualify a specific handheld electronic product.
Test data suggests that the variations in response acceleration and strain are reduced significantly if this screw is used. The comparability between different test sites, data acquisition methods, and board manufacturers has not been fully demonstrated by existing data. All assemblies shall be single side only unless the component is anticipated for use in mirror-sided board assemblies.
Therefore, options are provided for mounting just 1 or 5 components on the board using the following locations: All failures after each drop shall be logged. The standard is not meant to cover the drop test required to simulate shipping and handling related shock of electronic components or PCB assemblies. At least one board shall be used to adjust board mounting process such as paste printing, placement, and reflow profile.
BOARD LEVEL DROP TEST METHOD OF COMPONENTS FOR HANDHELD ELECTRONIC PRODUCTS
A visual inspection shall be performed on all boards for solder mask registration, contamination, and daisy chain connection. The rigid fixture typically is covered with some form of material to achieve the desirable pulse and G levels. This shall be accomplished by designing double sided boards with mirror component footprint on each side top and bottom of the board. For board Side A, the microvias in pads shall be created with laser ablation with via diameter b11 microns.
The glass transition temperature, Tg, of each dielectric material as well as of the composite board shall be b1111 or greater. One board shall also be used to measure the mechanical properties modulus, and Tg of the board at the component location using DMA and TMA method. The through holes shall have the drill diameter of microns and finished plated hole diameter of microns. The fundamental mode results in maximum displacements and is typically most damaging. This can occur if the PCB traces come off b11 board with component while maintaining electrical continuity.
Electrical continuity test shall also be performed on all mounted units to detect any opens or shorts.
The primary driver of these failures is excessive flexing of circuit board due to input acceleration to the board created from dropping the handheld electronic product. A total of 5 packages from the test lot shall h111 subjected to failure analysis to determine the root cause and to identify failure mechanism.
The capture pad diameter shall be jfsd22 least microns. The failure data can only be pooled together when they have been proved to be statistically equivalent.