Technical Library | 2007-03-13 14:28:27.0
This article tells what your electronic manufacturing service providers needs from you to prepare an accurate quotation for a typical printed circuit board assembly project.
Technical Library | 2015-04-08 11:10:47.0
An electronic schematic describes the electrical connectivity of a piece of equipment or an entire system. It is made up of symbols that represent individual components and contains electrical and mechanical information and their related connectivity, along with other important data. Information contained within the schematic is packaged into a printed circuit board (PCB) where the mechanical footprint is placed onto the board and connectivity information is graphically displayed. The more accurate the information contained in the schematic is and the clearer it is presented, the more it contributes to a robust printed circuit board.
Technical Library | 2009-12-09 19:47:15.0
For the mobile market some PCB assemblies have been converted to flex circuit assemblies, in part because flex circuit assembly can be twisted or bent per the application needs. Flex circuits offer the same advantages as conventional printed circuit boards: quality, reliability, and high density.
Technical Library | 2013-10-13 10:36:21.0
Designing circuit boards for selective robotic spraying of conformal coating can be straightforward if you follow some design rules. Follow them and you can save money and time in your application process. However, if the rules are not followed, the resultant circuit board design can challenge even the most sophisticated conformal coating system and its operator to achieve the finish desired.
Technical Library | 2024-01-08 21:31:01.0
The aim of this collection and interpretation is to develop an understanding of moisture in materials, especially in printed circuit boards, to know the effects on further processing and to be able to derive targeted corrective actions when moisture-related problems occur. In principle, the considerations are valid for all types of PCBs. Although these basic principles are of particular importance when working with flexible and rigid-flexible printed circuit boards; observing them can mean the difference between success or failure.
Technical Library | 1999-08-09 11:11:55.0
A great deal of controversy continues to surround the use of Hot Air Solder Leveling (HASL) in the production of printed circuit boards (PCBs). The financial burden, technological limitations and environmental issues surrounding the HASL process continue to grow. This requires an in-depth review by the printed circuit board manufacturing plant, as well as the assembly operation and instrument designers ( OEMs), to determine what alternative surface finishes are appropriate.
Technical Library | 2015-04-30 20:17:03.0
Higher-speed signal transmission is increasingly required on a printed circuit board to handle massive data in electronic systems. So, signal transmission loss of copper wiring on a printed circuit board has been studied. First, total signal loss was divided into dielectric loss and conductor loss quantitatively based on electromagnetic theory. In particular, the scattering loss due to surface roughness of copper foil has been examined in detail. And the usefulness of the copper foil with low surface roughness has been demonstrated.
Technical Library | 2024-01-08 18:36:01.0
The following aims lie behind the investigations described: The circuit board is an integrated structure made of metal and plastic. Like most integrated components enclosed in plastic, it absorbs water. When it is rapidly heated as, for example, in soldering technology temperature processes, it is a well known fact that the water will evaporate abruptly, leading to destruction. It is therefore essential that the circuit board be dried before these soldering processes. Circuit board manufacturers are extremely hesitant at providing instructions on drying their circuit boards. Information from the ZVEI [1] should also be regarded critically. The cardinal problem is the high temperature which is recommended for baking. If this is applied, the result is often de-lamination and distortion of the circuit boards. Corrosion and the formation of intermetallic phases of the metallic surfaces are also to be expected. The following investigates whether gentle drying at 45°C or 60°C and at low relative humidity achieves the same result as baking at high temperatures. The industry provides novel dry cabinets which are suitable for rapid drying at relative humidities below one percent.
Technical Library | 2021-03-24 01:26:05.0
In-circuit test (ICT) has remained one of the most popular and cost-effective test methods for medium and high volume printed circuit board assembly (PCBA) for many years. This is due to its component-level fault diagnosis capability- and its speed.
Technical Library | 2011-03-17 15:29:54.0
Accurate, models for vias in a multilayer circuit board are necessary to predict link performance in the GHz regime. This paper describes a methodology to build a high bandwidth, scalable first approximation circuit model using simple transmission lines o