An Optimized Assembly Solution for Surface Mount Led Module
Authors: ChinFei Ng, Shirley Ng and Patrick Aun Company: Sanmina (M) Sdn Bhd Date Published: 4/12/2016
Abstract: This paper illustrates the SMT challenges of assembling LED module onto the main board. The placement accuracy and alignment of LED module onto the main board is extremely critical especially after rubber boot housing assembly as minor rotational skew of more than 1 degree could lead to product functional failure due to light leakage. Hence, a team collaboration of PCB Designer, Design Engineer and NPI Process Engineer was involved to develop and evaluate two different designs of LED module (LGA with pre-bump and Castellation with center ground) to mitigate the LED module rotational skew issue after reflow. The new designed LED module has been established to meet both design requirements and process perspective. The team has put together to successfully drive the issue for closure after tremendous efforts. The CMM results showed that the alignment consistency of both LGA type and castellated type LED modules is meeting Cp>2 and Cpk>1.5. Nevertheless, LGA type with pre-bump design was selected due to better rubber housing assembly from engineering LED module evaluation. This project has achieved 13% scrap cost reduction of more than US$20k annually by optimizing the LED module assembly approach.