Understanding the Impact of PCB Changes in the Latest Published JEDEC Board Level Drop Test Method

2018 ◽  
Author(s):  
Varun Thukral ◽  
J.J.M. Zaal ◽  
R. Roucou ◽  
J. Jalink ◽  
R.T.H.. Rongen
Keyword(s):  
Test Method ◽  
Drop Test ◽  
Board Level ◽  
The Impact

Failure Analysis of Halogen-Free Printed Circuit Board Assembly Under Board-Level Drop Test

2012 ◽  
Vol 134 (1) ◽  
Author(s):  
Hung-Jen Chang ◽  
Chau-Jie Zhan ◽  
Tao-Chih Chang ◽  
Jung-Hua Chou
Keyword(s):  
Printed Circuit Board ◽  
Drop Test ◽  
Circuit Board ◽  
Printed Circuit Board Assembly ◽  
Printed Circuit ◽  
Plastic Ball ◽  
Circuit Board Assembly ◽  
Halogen Free ◽  
Board Level ◽  
The Impact

In this study, a lead-free dummy plastic ball grid array component with daisy-chains and Sn4.0Ag0.5Cu Pb-free solder balls was assembled on an halogen-free high density interconnection printed circuit board (PCB) by using Sn1.0Ag0.5Cu solder paste on the Cu pad surfaces of either organic solderable preservative (OSP) or electroless nickel immersion gold (ENIG). The assembly was tested for the effect of the formation extent of Ag3Sn intermetallic compound. Afterward a board-level pulse-controlled drop test was conducted on the as-reflowed assemblies according to the JESD22-B110 and JESD22-B111 standards, the impact performance of various surface finished halogen-free printed circuit board assembly was evaluated. The test results showed that most of the fractures occurred around the pad on the test board first. Then cracks propagated across the outer build-up layer. Finally, the inner copper trace was fractured due to the propagated cracks, resulting in the failure of the PCB side. Interfacial stresses numerically obtained by the transient stress responses supported the test observation as the simulated initial crack position was the same as that observed.

Hybrid Simulation Method for PWB Level Drop Tests

2005 ◽  
Author(s):  
Jiansen Zhu ◽  
Esa Hussa ◽  
Juscelino Okura ◽  
Santosh Shetty
Keyword(s):  
Large Deformation ◽  
Simulation Method ◽  
Standard Test ◽  
Test Method ◽  
Drop Test ◽  
Nonlinear Material ◽  
Time Curve ◽  
Impulse Duration ◽  
Drop Tests ◽  
The Impact

PWB level drop tests are widely used as a standard test method to evaluate the reliability of PWB and packages under drop conditions (JEDEC Standard JESD22-B104-A). The drop height and test setup need be adjusted in order to achieve the requirements of a peak shock of 1500g and an impulse duration of 0.5 ms. Generally, the ground need be covered with a thin layer of rubber pad to absorb some of the impact energy. However, this rubber pad will bring challenges for modelling due to large deformation, nonlinear hyperelasticity, and contact. And sometimes, it may also cause the convergence problem. Therefore, a hybrid drop simulation method was developed. This hybrid method can not only circumvent the difficulties mentioned, but also increase the efficiency and reduce the CPU time of PWB drop simulation. When simulating a PWB board level drop test, generally, not only the PWB and the components assembled on it need be modelled, but also the drop vehicle, rubber pad, and ground should be included in the model. For the hybrid drop simulation, however, only part of drop vehicle need be modeled and there is no need to model the ground and the contact between the ground and the drop vehicle. Then an acceleration time curve measured from drop test is applied to the hybrid model so that the responses of the model will mimic the real drop situation. In this way, not only the simulation time is reduced due to smaller model sizes, but also can some difficulties related to large deformation, contact, and nonlinear material properties be avoided. Finally, a comparison of a bare PWB and a populated PWB drop cases was used to validate this hybrid drop simulation method. A reasonable correlation was achieved.

Analysis on the Effect of Input Impact Profiles in Drop Test

2007 ◽  
Author(s):  
Jiang Zhou ◽  
Ratna P. Niraula ◽  
Kendrick Aung
Keyword(s):  
Dynamic Response ◽  
Impact Load ◽  
Block Diagram ◽  
Input Pulse ◽  
Drop Test ◽  
System Level ◽  
System Response ◽  
Time Duration ◽  
Board Level ◽  
The Impact

The objective of this paper is to develop an analytical or mathematical predicative model for the evaluation of dynamic response of a structural element in a microelectronic or an optoelectronic product to an impact load occurring as a result of drop or shock test. Closed-form theoretical solution was obtained to simulate the board level drop test. The block diagram based SIMULINK analysis was introduced to determine the response with various impact configurations for the system level drop test as well. This study will help reliability engineers to design the impact input profiles and obtain the desired responses, and to calibrate and validate finite element analysis results quickly for both board level and system level drop test. It was found that time durations of the input profiles play an important role in the dynamic response. The system response can be designed by carefully choosing the impact time duration. Certain input pulse time results in the response with very low ringing after first or second peaks.

Drop Test Simulation for the Component-Level Reliability of Module Packages

2010 ◽  
Vol 2010 (1) ◽  
pp. 000220-000226
Author(s):  
Yu Gu ◽  
Daniel Jin
Keyword(s):  
Parametric Modeling ◽  
Drop Test ◽  
Parametric Models ◽  
Component Level ◽  
Test Board ◽  
Module Size ◽  
Drop Tests ◽  
Explicit Dynamic ◽  
Board Level ◽  
The Impact

The component-level drop reliability of micro-electronic packages has been a concern. Proper modeling approaches can significantly reduce the time and costs and provide valued data support not only on the failure analysis but also on product development. Based on finite element methods, the presented study performed explicit dynamic drop modeling to simulate the actual drop tests using ANSYS and LS-DYNA. A generic over-molded LGA (land grid array) module was selected and 3D parametric models were utilized to carry out the study. As in the actual drop test, the standard JEDEC test board and JEDEC drop condition were applied. The over-molded modules together with the test board under 1500G gravity was simulated to identify the failure locations. The results were fairly correlated to the actual FA observation. Potential key factors such as solder pad size, pitch size, module size, and thickness were studied through the parametric modeling. The impact of board side defect, such as solder void, was also studied because it is common to have this kind of defect in assembly. Besides component-level drop reliability, we also studied the board-level drop reliability by investigating the LGA solder stress.

A Study on Repetitive Drop Test Method and for Electronic Component

2007 ◽  
Author(s):  
Qiang Yu ◽  
Masato Fujita ◽  
Tsuyoki Shibata ◽  
Takayoshi Katahira ◽  
Masaki Shiratori
Keyword(s):  
High Stress ◽  
Fem Simulation ◽  
Strain Analysis ◽  
Test Method ◽  
Drop Test ◽  
Electronic Components ◽  
Flat Bottom ◽  
Supporting Condition ◽  
Board Level ◽  
Load Conditions

In recent years, mobile phones have been miniaturized, so electronic components with high I/O count have been changed from QFP/SOIC to BGA/LGA. However BGA/LGA tends to have weak reliability for drop impact, and the drop reliability needs to be improved. For that, board level drop reliability has an important role in order to evaluate drop reliability for electronic components excluding influence from phone mechanics. This study focuses on the characterization of the test methods using experimental test, strain analysis and FEM simulation. In this paper, board level drop test shows drop a fixture with a component assembled on PWB. The drop test using a fixture with a flat bottom lacked of repeatability of failed drop count, and it was improved by adding hemisphere at the center on fixture bottom to reduce the influence by variation of falling posture angle, and strain analysis and the drop experimental proved it, too. The deformations of the fixture influence the test results, because the deformation of fixture caused high stress on solder joints. For that, the method to exclude the influence of fixture deformation was studied, and it was found that the influence can be decreased by supporting condition of PWB with a free-sliding end or the new design of the fixture. On the other hand, the effect of height of drop, mass of fixture, and supporting condition on the drop test, can be thought as the acceleration factors for the dropping load conditions. The drop tests were done in many load conditions. The results were analyzed by strain analysis and FEM simulation. As a result, an accelerating ratio can be evaluated by predicting the effect of these factors, and effective dropping test can be conduct without increasing the dropping height exceedingly.

Characterization of Fine Pitch CSP Solder Joints Under Board-Level Free Fall Drop (BFFD)

2005 ◽  
Author(s):  
Dongji Xie ◽  
David Geiger ◽  
Dongkai Shangguan ◽  
Daniel T. Rooney ◽  
Louis J. Gullo
Keyword(s):  
Failure Modes ◽  
Solder Joints ◽  
Cellular Phone ◽  
Free Fall ◽  
Drop Test ◽  
Strain Level ◽  
Board Structure ◽  
Element Analysis ◽  
Board Level ◽  
The Impact

This paper presented a board-level free fall drop (BFFD) to simulate product free fall drop (PFFD). In BFFD, the board structure is very close to the actual cellular phone boards with similar size. The board edges were reinforced by metal frame and screws similar to the cellular phone housing. The drop test was performed to characterize the solder joints of 0.4mm pitch chip scale package (CSP) packages. To charaterize the stress level, the acceleration was measured and the free drop test was performed for more than 140 boards with different CSP structures. The plastic strain of solder joints in different location was calculated using finite element analysis (FEA). It was found that the strain level is both location and component dependent. This strain level will determine the probability of drop test failure in terms of number of drops to failure. The impact of component type, body size and component location was investigated by both experimentally and FEA. Through drop test, the number of drop before failure (MDBF) were recorded and compared across various CSPs. Failure analysis was also performed to confirm the failure modes.

scholarly journals Evaluation of Energy Absorption Capabilities of Polyethylene Foam under Impact Deformation

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3613
Author(s):  
Baohui Yang ◽  
Yangjie Zuo ◽  
Zhengping Chang
Keyword(s):  
Energy Absorption ◽  
Failure Modes ◽  
High Strain ◽  
Early Stage ◽  
High Energy ◽  
Test Method ◽  
Test Theory ◽  
Strain Rates ◽  
Impact Properties ◽  
The Impact

Foams are widely used in protective applications requiring high energy absorption under impact, and evaluating impact properties of foams is vital. Therefore, a novel test method based on a shock tube was developed to investigate the impact properties of closed-cell polyethylene (PE) foams at strain rates over 6000 s−1, and the test theory is presented. Based on the test method, the failure progress and final failure modes of PE foams are discussed. Moreover, energy absorption capabilities of PE foams were assessed under both quasi-static and high strain rate loading conditions. The results showed that the foam exhibited a nonuniform deformation along the specimen length under high strain rates. The energy absorption rate of PE foam increased with the increasing of strain rates. The specimen energy absorption varied linearly in the early stage and then increased rapidly, corresponding to a uniform compression process. However, in the shock wave deformation process, the energy absorption capacity of the foam maintained a good stability and exhibited the best energy absorption state when the speed was higher than 26 m/s. This stable energy absorption state disappeared until the speed was lower than 1.3 m/s. The loading speed exhibited an obvious influence on energy density.

scholarly journals Laboratory experiment on the nano-TiO2 photocatalytic degradation effect of road surface oil pollution

2020 ◽  
Vol 9 (1) ◽  
pp. 922-933
Author(s):  
Qing’e Wang ◽  
Kai Zheng ◽  
Huanan Yu ◽  
Luwei Zhao ◽  
Xuan Zhu ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Oil Pollution ◽  
Road Surface ◽  
Test Method ◽  
Driving Safety ◽  
The Road ◽  
Road Surfaces ◽  
The Many ◽  
The Impact ◽  
Degradation Effect

AbstractOil leak from vehicles is one of the most common pollution types of the road. The spilled oil could be retained on the surface and spread in the air voids of the road, which results in a decrease in the friction coefficient of the road, affects driving safety, and causes damage to pavement materials over time. Photocatalytic degradation through nano-TiO2 is a safe, long-lasting, and sustainable technology among the many methods for treating oil contamination on road surfaces. In this study, the nano-TiO2 photocatalytic degradation effect of road surface oil pollution was evaluated through the lab experiment. First, a glass dish was used as a substrate to determine the basic working condition of the test; then, a test method considering the impact of different oil erosion degrees was proposed to eliminate the effect of oil erosion on asphalt pavement and leakage on cement pavement, which led to the development of a lab test method for the nano-TiO2 photocatalytic degradation effect of oil pollution on different road surfaces.

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