Technical Library | 2019-05-31 14:19:24.0
ACI Technologies (ACI) characterized the reliability of surface mount RF components. The RF frequency band of interest was the X band (10.7 to 11.7GHz). A two pronged test for reliability of circuit card assemblies (CCA) was designed for both extreme thermal cycling and vibration. The rapid thermal cycling and extreme vibration testing simulates the total stress encountered by the assembly over the life of the product but accomplishes it in a relatively short period of time. In order to perform the reliability testing, a test vehicle consisting of a printed circuit board with test structures and components, was designed, fabricated, and assembled at ACI.
Technical Library | 2024-06-20 22:53:23.0
A leading electronic hearing device manufacturer reduced UV precise coating cycle time by 79% with advanced automation. A manual process of hand brushing UV coating onto components was replaced by an automated solution from Nordson to increase production volumes, improve quality, and reduce costs for this complex application. Download the paper to learn the details of the application.
Technical Library | 2020-09-02 14:34:23.0
Atomic layer deposition (ALD) is a process of creating coatings on a molecular layer by layer basis. Using an iterated sequence of self-saturating deposition cycles that are self-terminating, a single layer can be deposited at a time, allowing for highly uniform films with complete conformality. The composition of the film typically used for coating printed wiring boards (PWBs) is a high alumina (Al2O3) sequential deposition of alumina and titania capped with a corrosion protective titanium aluminate layer, most notably ALD-Cap from Sundew Technologies, LLC. Rework is a process of restoring an electronics assembly to full functionality to prolong equipment life and reduce the amount of scrap. The process typically involves:
Technical Library | 2012-12-17 22:05:22.0
Package on Package (PoP) has become a relatively common component being used in mobile electronics as it allows for saving space in the board layout due to the 3D package layout. To insure device reliability through drop tests and thermal cycling as well as for protecting proprietary programming of the device either one or both interconnect layers are typically underfilled. When underfill is applied to a PoP, or any component for that matter, there is a requirement that the board layout is such that there is room for an underfill reservoir so that the underfill material does not come in contact with surrounding components. The preferred method to dispensing the underfill material is through a jetting process that minimizes the wet out area of the fluid reservoir compared to traditional needle dispensing. To further minimize the wet out area multiple passes are used so that the material required to underfill the component is not dispensed at once requiring a greater wet out area. Dispensing the underfill material in multiple passes is an effective way to reduce the wet out area and decrease the distance that surrounding components can be placed, however, this comes with a process compromise of additional processing time in the underfill dispenser. The purpose of this paper is to provide insight to the inverse relationship that exists between the wet out area of the underfill reservoir and the production time for the underfill process.
Technical Library | 2009-05-14 13:57:43.0
Is screen printing technology able to keep pace with rising quality demands and increasingly complex board layouts? Or, is new jet printing technology ready to fill the gap? A comparison study between the two methods reveals some interesting differences. Screen printers offer some possibilities for optimizing solder paste deposits, but optimization is far easier and quicker with the jet printer. At the same time, the ability to print individualized deposits on every single pcb pad may be the ultimate answer to the growing quality challenge.
Technical Library | 2020-12-10 15:49:40.0
Electronic assemblies should have longer and longer service life. Today there are partially demanded 20 years of functional capability for electronics for automotive application. On the other hand, smaller components, such as resistors of size 0201, are able to endure an increasing number of thermal cycles until fail of solder joints, so these are tested sometimes up to 4000 cycles. But testing until the end of life is essential for the determination of failure rates and the prognosis of reliability. Such tests require a lot of time, but this is often not available in developing of new modules. A further acceleration by higher cycle temperatures is usually not possible, because the materials are already operated at the upper limit of the load. However, the duration can be shortened by the use of liquids for passive tests, which allow faster temperature changes and shorter dwell times because of better heat transfer compared to air. The question is whether such tests lead to comparable results and what failure mechanisms are becoming effective. The same goes for active temperature cycles, in which the components itself are heated from inside and the substrate remains comparatively cold. This paper describes the various accelerated temperature cycling tests, compares and evaluates the related degradation of solder joints.
Technical Library | 2001-04-24 10:47:02.0
Board-level circuits today routinely run at speeds of 100 MHz or more and are composed of dozens of complex interacting VLSI components. To design such circuits in a timely and correct manner it is necessary to pay close attention to circuit timing early in the design cycle. At fast clock speeds, managing component and interconnect propagation delay becomes a key aspect of circuit design. It is imperative that the critical paths on a circuit and the slack available for interconnect delay consumption be identified early, and drive subsequent stages in the design flow.
Technical Library | 2024-02-06 14:36:04.0
Quality monitoring for verifiable, high-precision application of adhesives and sealants now begins with detecting the position of the component. Dispensing systems are in continuous use and have to work with 100 percent accuracy. And this level of accuracy must be verifiable. Demands on electronic components continue to escalate as these components also need to operate continuously and flawlessly, especially in the automotive and medical sectors. At the same time, there is increasing pressure to automate as companies are looking to achieve the shortest possible cycle times and maximum output.
Technical Library | 2023-02-15 16:00:16.0
With regard to potting, the design of electronic assemblies and components has a significant impact on economical and sustainable production. Key aspects in this respect are pottability, material use, cycle times, quality and the process technology needed. Optimized, bubble-free potting contributes greatly to the function and longevity of products. It is best practice during the design and development phases therefore to follow the potting tips contained in this White Paper.
Technical Library | 2020-03-04 23:53:17.0
Critical to maintaining quality control in high-throughput screening is the need for constant monitoring of liquid-dispensing fidelity. Traditional methods involve operator intervention with gravimetric analysis to monitor the gross accuracy of full plate dispenses, visual verification of contents, or dedicated weigh stations on screening platforms that introduce potential bottlenecks and increase the plate-processing cycle time. We present a unique solution using open-source hardware, software, and 3D printing to automate dispenser accuracy determination by providing real-time dispense weight measurements via a network-connected precision balance. This system uses an Arduino microcontroller to connect a precision balance to a local network. By integrating the precision balance as an Internet of Things (IoT) device, it gains the ability to provide real-time gravimetric summaries of dispensing, generate timely alerts when problems are detected, and capture historical dispensing data for future analysis. All collected data can then be accessed via a web interface for reviewing alerts and dispensing information in real time or remotely for timely intervention of dispense errors. The development of this system also leveraged 3D printing to rapidly prototype sensor brackets, mounting solutions, and component enclosures.
