- design007 Magazine
Latest IssuesCurrent Issue
The Standards of Design
Our expert contributors discuss how PCB designers can utilize standards to save time and money, not to mention frustration. We also spotlight the newly updated version of the IPC Checklist, a handy guide that illustrates which standards cover which topics, from front-end design through assembly.
Rigid-flex: Designing in 3D
In this month’s issue, our expert contributors share their best tips, tricks and techniques for designing rigid-flex circuits. If you’re a rigid board designer considering moving into the 3D world of rigid-flex, this issue is just what the doctor ordered!
- Events||| MENU
- design007 Magazine
Enhancing Thermal Performance of CSP Integrated CircuitsFebruary 24, 2016 | Nicholaus Smith, Integrated Device Technology
Estimated reading time: 1 minute
In the portable electronics market, power management integrated circuits (PMICs) are increasingly found being packaged into ball grid array (BGA) and chip scale packages (CSP) for their lower material costs, improved electrical performance (no bond wire impedances), and smaller form factors. These advantages do not come without compromise: The silicon die of CSPs are no longer in direct contact with large heat-spreading thermal paddles (E-PADs) used for electrical and thermal conduction.
This is the primary performance trade-off; because the IC substrate is not in contact with an E-PAD there is no high-conductivity direct thermal connection from the substrate to the heat-spreading copper planes on the PCB. This article will discuss PCB level methods that will lower the operating temperature of CSP devices by examining methods to transfer heat from the source and transport it to the ambient environment by lowering thermal resistance of the CSP IC. There are usually multiple ways to enhance the performance while simultaneously lowering the operating temperature that can be incorporated into new boards or revisions of existing boards.
In order to meet size and weight requirements, constraints of portable electronic designs often force PCB designers to reduce the size of components and PCB real estate area. To meet these demands, the use of CSP packages to shrink the PCB area needed is a common change in designs. As a result of the reduction of total PCB area, the available options to move heat and route high-power PCB traces is also reduced. Furthermore, the thermal performance cannot be matched when a QFN is compared to an equivalent CSP package; therefore, it is imperative that the PCB is designed to optimize heat transfer from the CSP to the PCB, which in turn dissipates it into the atmosphere. The parameter measuring the heat conductivity is the junction-to-ambient thermal resistance specification, Theta-JA (ӨJA (˚C/W)).
To read this entire article, which appeared in the January issue of The PCB Design Magazine, click here.
The "Global Copper Clad Laminates Market (by Type, Application, Reinforcement Material, & Region): Insights and Forecast with Potential Impact of COVID-19 (2023-2028)" report has been added to ResearchAndMarkets.com's offering.
The SCHMID Group, a global solution provider for the high-tech electronics, photovoltaics, glass and energy systems industries, will be exhibiting at productronica in Munich from November 14 – 17, 2023.
The topic of intrinsic copper structure has been largely neglected in discussions regarding the PCB fabrication quality control process. At face value, this seems especially strange considering that copper has been the primary conductor in all wiring boards and substrates since they were first invented. IPC and other standards almost exclusively address copper thickness with some mild attention being paid to surface structure for signal loss-mitigation/coarse properties.
At PCB West, I sat down for an interview with John Andresakis, the director of business development for Quantic Ohmega. I asked John to update us on the company’s newest materials, trends in advanced materials, and the integration of Ticer Technologies, which Quantic acquired in 2021. As John explains, much of the excitement in materials focuses on laminates with lower and lower dielectric constants.
Printed circuit board (PCB) reliability testing is generally performed by exposing the board to various mechanical, electrical, and/or thermal stimuli delineated by IPC standards, and then evaluating any resulting failure modes. Thermal shock testing is one type of reliability test that involves repeatedly exposing the PCB test board to a 288°C pot of molten solder for a specific time (typically 10 seconds) and measuring the number of cycles it takes for a board’s copper layer to separate from the organic dielectric layer. If there is no delamination, fabricators can rest assured that the board will perform within expected temperature tolerances in the real world.