For decades, D-subminiature connectors have been the interconnect of choice in many electronic systems. Over time, these connectors have evolved to meet changing requirements in a wide variety of applications.
D-subminiature connectors are available in six package sizes. Each package size can be configured with standard and high-density contact spacing, as well as mixed contact densities. A broad range of accessories is available to support the use of these connectors throughout the manufacturing process and into the end use application.
Termination types include straight and right angle PCB mount; crimp and solder for cable termination; and straight and right angle press-fit. Multiple contact types, are including signal, power, coax, and high voltage. Fiber optic contact offerings will be made available in time. There are also many performance options available for best “cost-to-performance ratio” in any application.
Since D-subminiature connectors commonly have metal shells, they are a natural choice for applications requiring EMI and RFI shielding. Fixed connectors can be mounted directly to a panel. Back shells are available for free cable mount connectors. Many back shells offer EMI and RFI shielding characteristics.
In many applications, EMI/RFI shielded back shell offerings have not kept pace with requirements. These types of back shells tend to be large, bulky, and heavy. This is a problem in applications where weight reduction is a growing concern, such as the aerospace industry.
Many EMI/RFI hoods have a limited cable opening size. This creates a problem when high density contact configurations are used. As an example, shell size 6 D-Subminiature connectors offer 104 contacts. Back shells may not have a large enough cable opening to fully support the number of conductors that must be brought into the back shell. This is especially true when the cable includes twisted, shielded pairs that must terminated inside the back shell. The industry needed an improved EMI/RFI back shell.
To meet these challenges, Positronic industries developed a new generation back shell for D-Subminiature connectors. The “A” series back shell combines a number of features that meet the needs of many of today’s most challenging requirements of EMI/RFI protection for cable connectors.
Cable to cable options
Large Aperture, multiple grounding points and spacious interior
Space flight performance options
“A” Series back shell features include:
• Lightweight aluminum material with a zinc content of less then 1%, an important factor in applications restricting the use of zinc. Wall thickness provides a robust product while maintaining the goal of a lightweight back shell.
• A larger aperture and strain relief which is appropriate for high density wire bundles using twisted, shielded pairs. Cable clamps can be “spooned” to provide strain relief for smaller wire bundles. Wide form factor allows the user to easily meet bend radius requirements
• Up to six grounding points (depending on the size of the back shell) which are sized and shaped for use with 0.250 inch diameter ring terminals. Multiple ring terminals can be stacked under each grounding screw. Ground screw holes are pre-tapped for ease of installation. Ground screw holes are tapped through the body of the back shell which provides internal or external grounding options
• Spacious interior is shaped to facilitate wire routing inside the back shell. There are no internal obstructions toward the rear of the back shell which might prohibit wire routing or connector options
• The back shell offers a thumb grip to facilitate installation and removal in tight spaces
• Back shells are offered with jackscrews as well as a quick disconnect locking systems. Options allow back shell to board or panel locking as well as back shell to back shell locking
• Lightweight back shells are available with various performance levels including options for use in space flight applications.
As high reliability connector requirements continue to evolve, manufacturers must keep pace. The “A” series hood is an example of a product that has helped connector users in who need light weight and higher density connectors.