Technical Library | 2019-06-04 10:19:46.0
Interconnection technology relies very heavily on the ability of the conductors on a printed wiring assembly to maintain reliable signal integrity. Harsh environmental factors can precipitate a loss of conductivity due to oxidation and corrosion. Connections are typically soldered or inserted using pressure fitted connectors to obtain enough surface contact to meet the electrical conductivity requirements. In pressure contacts, surface integrity is especially critical where the abrasive effects of retraction and insertion can wear off the metallic finish from the contact area. This can expose the underlying copper or nickel and lead to increased resistance at the contact points. These types of conductors are frequently found in card edge connectors where the terminations are plated with a layer of nickel and gold (frequently referred to as gold fingers). A hard gold is typically used containing very small amounts of nickel and cobalt to increase the wear resistance.
Technical Library | 2019-08-01 10:58:32.0
Optical fibers transmit information in the form of pulses of light. The advantages of optical fibers over traditional copper wires include: higher throughput, greater signal distance and speed, smaller cable mass and diameter, greater pull tension limit, and resistance to electromagnetic interference (EMI) and radio frequency interference(RFI). The disadvantages of fiber optics when compared to copper wires include: end-face defects, cleanliness, and the ease of attaching connectors to electronics assemblies (Figure 1).
Technical Library | 2019-11-13 13:53:50.0
Fiber optic harnesses appear simple, but they have been designed to maintain all of the critical areas of aligning two fibers and minimize the losses associated with a break in the transmission path. In order to understand how the connectors overcome alignment issues, we must first understand the issues. Fiber optic communications networks use specific wavelengths of light (or colors) to transmit information through a clear fiber at high speed. They use the property of internal reflection along the fiber’s axis to contain the light and keep the optical power high enough to be detected at the receiving end.
Technical Library | 2019-12-05 13:30:46.0
Conformal coatings are regularly employed to protect the surface of a soldered printed circuit board assembly from moisture, chemicals in the PCBA's service environment, and foreign objects or debris. Conformal coatings are nonconductive and therefore cannot be placed on any location where electrical contact will be required, such as connector pins, test points, and sockets. Conformal coatings are also not permitted on any mechanical interface location, such as mounting holes or brackets, to assure the proper fit between items in the final assembly. In order to apply conformal coatings to an assembly and comply with the restrictions on keep-out areas, masking is employed to protect those surfaces.
Technical Library | 2019-06-06 13:40:47.0
Legacy electronics assemblies, such as through-hole (Figure 1) and connectorized component packages, are robust and prevalent throughout industry. However, each of these assembly methods have reached their limits in terms of weight, volume, reliability, and most importantly cost. With cost reduction of assemblies now the primary focus area throughout the electronics industry, there is more of a need than ever to implement the latest advancements in surface mount technology (SMT) into electronics assembly designs. Although SMT has been utilized in the electronics industry for many years, implementation of the technology is still in the ever-evolving process of reducing component footprint size, component spacing, and component I/O pitch. Implementation of the most up-to-date SMT processes provides optimal weight, volume, and cost savings, for any type of assembly.
Technical Library | 1999-05-06 15:36:33.0
The success of surface-mount technology has not meant the end of through-hole connectors. For reasons ranging from availability to user concerns over reliability, through-hole connectors remain widely used.
Technical Library | 2008-11-27 01:25:25.0
Military electrical connectors have traditionally used very conservative design rules that provide the ruggedization needed for harsh military use environments. Commercial electronic connectors have typically used less conservative design rules that.
Technical Library | 2010-11-06 02:44:38.0
An increasing number of video equipment is running at Gigabit rates today. They are interconnected through relatively large size coaxial BNC connectors. While these connectors are in general of good quality, their performance in the equipment depends on
Technical Library | 2010-08-26 19:45:44.0
The advantages of the Compression Mount Technology (CMT) when using AdvancedTCA and MicroTCA connectors.
Technical Library | 2020-05-07 03:46:27.0
The selective soldering process has evolved to become a standard production process within the electronics assembly industry, and now accommodates a wide variety of through-hole component formats in numerous applications. Most through-hole components can be easily soldered with the selective soldering process without difficulty, however some types of challenging components require additional attention to ensure optimum quality control is maintained. Several high thermal mass components can place demands on the selective soldering process, while the use of specialized solder fixtures and/or pallets often places an additional thermal demand on the preheating process. Fine-pitch through-hole components and connectors place a different set of demands on the selective soldering process and typically require special attention to lead projection and traverse speed to minimize bridging between adjacent pins. Dual in-line memory module (DIMM) connectors, compact peripheral component interface (cPCI) connectors, coax connectors and other high thermal mass components as well as fine-pitch microconnectors,can present challenges when soldered into backplanes or multilayer printed circuit board assemblies. Adding to this challenge, compact peripheral component interface connectors can present additional solderability issues due to their beryllium copper termination pins.