for connection to the PCB in order to be suitable for soldering, the basic terminal concept, bit-by-bit set up and connection of the individual conductors have not changed. Today, PCB terminals and PCB connectors represent a
large range of solutions that are not optimal, neither for the PCB design nor for the manufacturing process. It is a fact, however, that PCB terminals represent a termination system that is fully accepted for single conductors. The terminal approaches the device from an installation world and transfers its concepts to the device. And these installation aspects are crucial for the device’s installation at the end customer. A purely mezzanine solution is not fi eld installable. If
the path ended at the mezzanine connector, universal use in industrial devices would not be possible.
interface connectors are long-lived products whose format is determined by the technology of the actual interfaces. In the fi eldbus sector, for example, industry can look back on 20 years of RS 485 connectivity using 9-pole D-Sub connectors.
Connectors on a backplane are also linked with the
backplane technology’s innovation cycles. For this reason, certain connector concepts have been retained across a number of generations of PCBs because of the need for compatibility and the fact that end-users would have found an incompatible change unacceptable. The mezzanine application area is freer in this
regard, because the connectors are used for the internal confi guration of the devices. This freedom has meant that concepts have to measure up only in terms of the perfect device setup – and this they can do. Compatibility is not an issue here. But it isn’t quite this simple: industry relies on long-term
compatibility for the interfaces coming out of the devices, in order to allow simple and swift installation in the fi eld, even under the most adverse environmental conditions. As a result, future solutions must meet both the general
conditions of short innovation cycles inside the device and the consistency of the mating face outside the device for simple installation.
The pure installation solution The PCB terminals in use today were originally developed from designs motivated by the need to snap onto a carrier rail. This industrial device terminal technology was developed for installation in switch cabinets. Although the terminals have been reduced in size and modifi ed
September 2011 The metamorphosis
Fig.4. preLink® provides reliable termination of shielded system cables at data rates up to 10 Gbit/sA mezzanine connector sets the standard for the solution on the PCB as described. The primary idea here involves the fl exible design and the production process. However, industrial connectors are setting the standard for installation today. Connections offering the best of both worlds would be a desirable situation. Fortunately, this is now possible. A connector has two
sides, and in the mezzanine connector these two sides present the same termination technology. The PCB side is now the constant element, while the second side of the mezzanine connector now becomes the installation or cable side. This represents a metamorphosis of the mezzanine connector: there are now ‘board to cable’ and ‘board to wire’ connectors (Fig.1). In addition to the simple screw terminal or crimp
technology for single conductors and cables, new developments on the installation side include the following innovative technologies for termination: • HARAX®: An insulation displacement technique for
www.electronicscomponentworld.com /
www.electronicproductionworld.com EIU 25
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48