Technical Library | 1999-05-09 13:05:12.0
This Technical Note discusses the construction of solder tips, the various failure modes associated with tip plating (cracking, wear, corrosion, and dewetting), how to diagnose those failure modes, and specific practices that can be taken to minimize or eliminate each one.
Technical Library | 2012-04-26 18:52:37.0
First presented at IPC Apex Expo 2012. The reliability, as tested by thermal cycling, of printed wire boards (PWB) are established by three variables; copper quality, material robustness and design. The copper quality was most influential and could be eva
Technical Library | 2014-04-10 18:04:04.0
This paper is meant to be a guide and a reference to new and old members alike who wish to know about, understand, and improve on the decisions made and processes implemented to build the current solar panels. The following paragraphs in the introduction will lay out background information on solar panels and cube satellites. This entire document was written with the idea that the reader will be able to follow the decisions made to construct the solar panels and then with this knowledge find areas of the project for improvement.
Technical Library | 2020-01-22 22:52:02.0
Flip chip assembly techniques bring a wide range of benefits: Reduced parasitic interconnection between the semiconductor die and package. Provides a high final assembly integrity density. Minimize the interconnection length, providing better electrical performances, especially for high speed signals. Reduce the device size and weight,…, etc. But there is no dedicated inspection requirements nor DPA standard which address all the necessary aspects associated to this construction type or only cover partially the topics to be inspected.
Technical Library | 2016-08-04 10:34:35.0
With the onset of 1900’s, the novelty of printed circuits boards got started with a profound concept of constructing an electrical path on an isolated surface of a board. The initial trend of printed circuit board got into a vain to develop and upgrade the radios and gramophones. Gradually the notion of ‘Through Hole Technique’ came into picture to produce a double sided PCB. In mid 1990’s the idea of auto assembly process was introduced by PCB Manufacturer USA. This was a point of modern touch to enhance the fabrication process with automated soldering technique. The research and development picked up a pace for end to end electronic solutions for defense and US army.
Technical Library | 2014-11-13 19:23:50.0
With increasing power loss of electrical components, thermal performance of an assembled device becomes one of the most important quality factors in electronic packaging. Due to the rapid advances in semiconductor technology, particularly in the regime of high-power components, the temperature dependence of the long-term reliability is a critical parameter and has to be considered with highest possible care during the design phase (...) The aim of this paper is to give a short overview about standard thermal solutions like thick copper, thermal vias, plugged vias or metal core based PCBs. Furthermore, attention will be turned on the development of copper filled thermal vias in thin board constructions...
Technical Library | 2008-03-18 12:36:31.0
This paper examines the construction of a notebook mainboard with more than 2000 components and no wave soldering required. The board contains standard SMD, chipset BGAs, connectors, through hole components and odd forms placed using full automation and soldered after two reflow cycles under critical process parameters. However, state of the art technology does not help if the process parameters are not set carefully. Can all complex BGAs, THTs and even screws be soldered on a single stencil? What will help us overcome bridging, insufficient solder and thombstoning issues? This paper will demonstrate the placement of all odd shape components using pin-in-paste stencil design and full completion of the motherboard after two reflow cycles.
Technical Library | 2016-08-11 01:21:34.0
Be it a residential building, hospital, shopping mall, hotel, school, educational institution or any kind of a building, the security of the building is a prime facet to get a complete building solution. This also includes protecting the building, its assent and the human life from the airborne toxic industrial chemical, radiological and biological attacks or any accidental release apart from fire, water, earthquake and other security concerns. For these high value security solutions, the upgraded technology for the building safety system is now a top priority, especially in the commercial building sector and residential constructions. To introduce a completely new concept and a unique solution, it is necessary to focus on the dynamic electronic design and manufacturing solution in consultation with the custom PCB experts.
Technical Library | 2019-02-06 22:02:08.0
The High Density Packaging (HDP) user group has completed a project to evaluate the majority of viable Dk (Dielectric Constant)/Df (Dissipation Factor) and delay/loss electrical test methods, with a focus on the methods used for speeds above 2 GHz. A comparison of test methods from 1 to 2 GHz through to higher test frequencies was desired, testing a variety of laminate materials (standard volume production with UL approval, low loss, and "halogen-free" laminate materials). Variations in the test board material resin content/construction and copper foil surface roughness/type were minimized. Problems with Dk/Df and loss test methods and discrepancies in results are identified, as well as possible correlations or relationships among these higher speed test methods.
Technical Library | 2019-03-06 21:26:14.0
Electronic assemblies use a large variety of polymer materials with different mechanical and thermal properties to provide protection in harsh usage environments. However, variability in the mechanical properties such as the coefficient of thermal expansion and elastic modulus effects the material selection process by introducing uncertainty to the long term impacts on the reliability of the electronics. Typically, the main reliability issue is solder joint fatigue which accounts for a large amount of failures in electronic components. Therefore, it is necessary to understand the effect of polymer encapsulations (coatings, pottings and underfills) on the solder joints when predicting reliability.This paper presents the construction and validation of a thermo-mechanical tensile fatigue specimen. The thermal cycling range was matched with potting expansion properties in order to vary the magnitude of tensile stress imposed on solder joints
