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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During the test, the shock pulse shall be measured for each drop to ensure iesd22 input pulse remains within the specified tolerance. In that case, the components shall be mounted on each side of the board. Theoretically, the drop height needed to achieve the appropriate G levels can be determined by equation below where H is the drop height and C is the rebound co-efficient 1. The overall board size shall be b11 X 77 mm that can accommodate up to 15 components of same type in a 3 row by 5 column format.
Component length and width. There shall be four holes on the board to be used for mounting board on drop test fixture. A visible partial separation of component from the test board, even without a significant increase in resistance or intermittent discontinuity, shall also be considered as a failure. The glass transition temperature, Tg, of each dielectric material as well as of the composite board shall be oC or greater.
There shall be 20 plated through holes per square centimeter in the component region. Ford Packaging Drop Te The free-fall drop height of the drop n111 needed to attain the prescribed peak acceleration and pulse duration. Drop testing on other board orientation is not required but may be performed if deemed necessary.
A packaged semiconductor device.
BOARD LEVEL DROP TEST METHOD OF COMPONENTS FOR HANDHELD ELECTRONIC PRODUCTS | JEDEC
Since the dynamic response of the board may be affected by the mass jesd222 stiffening of the connector, it is recommended that no connectors are used and wires are directly soldered to the jed22.
In case of non-daisy chain die, a mechanical dummy die must be used inside the package to simulate the actual structure of the package.
This plate will serve as the mounting structure for the PCB assemblies. An electrical discontinuity of resistance greater than ohms lasting for 1 microsecond or longer.
This is the applied shock pulse to the base plate and shall be measured by accelerometer mounted at the center of base plate or close to the support posts for the board. The dielectric materials shall meet the mechanical properties requirements as given in Table 2. The component materials, dimensions, and assembly processes shall be representative of typical production device.
A continuity test instrument capable of detecting electrical discontinuity of resistance greater than ohms lasting for 1 microsecond or longer. The x, y location of the center of each component location is listed in Table 4, using the center of lower left screw hole as datum.
This includes all traces making contact with solder joint interconnect as well as all internal layers. This shall be accomplished by designing double sided boards with mirror component footprint on each side top and bottom of the board.
Since the length of shoulder is 3. This is required as typical PCB assemblies used in handheld electronic systems are constructed using high density, buildup technology.
jese22 Additional strain gages may also be mounted at different locations on the board to fully characterize the strain response of the assembly. It should be noted, however, that any additional mass will add significant dynamic weight to the board and may alter its dynamic response.
Experiments with different strike surface may be needed to achieve the desired peak value and jesf22. All failures after each drop shall be logged. Plated through holes or edge fingers shall be provided on each end of the board for soldering wires, one for each side top and bottom of the board.
Board thickness, warpage, and pad sizes shall also be measured using a sampling plan.
Depending on number of components per board, Table 5 shall be used to determine the number of boards to be tested per component type. All assemblies shall be single side only unless the component is anticipated for use in mirror-sided board assemblies.
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.
BOARD LEVEL DROP TEST METHOD OF COMPONENTS FOR HANDHELD ELECTRONIC PRODUCTS
This is pictorially shown in Figure 3. No claims to be in conformance with this standard may be made unless all requirements stated in the standard are met. All components must be located within the 95 mm X 61 mm box shown by the dashed line in Figure 1 defined by the outer edges of all outer components.
Means shall be provided in the apparatus such as automatic braking mechanism to eliminate bounce and to prevent multiple shocks to the board. The through holes shall have the drill diameter of microns and finished plated hole diameter of microns.
The capture pad diameter shall be at least microns. However, a mix of different component sizes and styles shall not be used on the same board, as this will affect the dynamic response of the board, making the results difficult to analyze. The board assembly shall then be mounted on the drop test fixture using four screws.
Because of symmetric component design and support locations, grouping see Table 6 can be used for data analysis for boards mounted with 15 components refer Figure 1.
At least one board shall be used to adjust board mounting process such as paste printing, placement, and reflow profile. Multiple drops maybe required while adjusting the drop height and strike surface to achieve the specified G levels and pulse duration Gs, 0.
I recommend changes to the following: The daisy chain should either be done at the die level or by providing daisy chain links at the lead-frame or substrate level. The characterized board response acceleration, strain, and strain rate and its variation shall be documented and provided with the test data. Depending on the strike surface, same drop height may result in different G level and pulse duration.
Test data suggests that the variations in response acceleration and strain are reduced significantly if this screw is used. The selection of packages should cover different locations on the board.
The drop test shall be conducted by releasing the drop table from the pre-established height. The maximum number of drops shall be 30 irrespective of single or double-sided assembly. Effect of Thermal Agin