Eurocard Connectors per DIN 41612 and IEC 60603-2
DIN 41612 was a DIN standard for electrical connectors that are widely used in rack based electrical systems. The most widely known use of DIN 41612 connectors is in the VMEbus and NuBus systems. The standard has withdrawn in favor of international standards IEC 60603-2 and EN 60603-2.
DIN 41612 connectors are used in Pancon, STEbus,Futurebus, VMEbus, Multibus II, NuBus, VXI Bus,eurocard TRAM motherboards, and Europe Card Bus, all of which typically use male DIN 41612 connectors on Eurocards plugged into female DIN 41612 on the backplane in a 19-inch rack chassis.
Mechanical
The standard describes connectors which may have one, two or three rows of contacts, which are labelled as rows a, b and c. Two row connectors may use rows a+b or rows a+c. The connectors may have 16 or 32 columns, which means that the possible permutations allow 16, 32, 48, 64 or 96 contacts. The rows and columns are on a 0.1 inch (2.54 mm) grid pitch. Insertion and removal force are controlled, and three durability grades are available.
Often the female DIN 41612 connectors have press fit contacts rather than solder pin contacts, to avoid thermal shock to the backplane.
Electrical
The headline performance of the connectors is a 2 amp per pin current carrying capacity, and 500 volt working voltage. Both these figures may need to be de-rated according to safety requirements or environmental conditions.
Performance Classes
The DIN 41612 specification identifies 3 different classes or "levels"; it's more complicated than this, but, essentially: class 1 is good for 500 mating cycles; class 2 is good for 400 mating cycles, and, class 3 is good for 50 mating cycles.
NuBus (pron. 'New Bus') is a 32-bit parallel computer bus, originally developed at MIT and standardized in 1987 as a part of the NuMachine workstation project. The first complete implementation of the NuBus was done by Western Digital for their NuMachine, and for the Lisp Machines Inc. LMI Lambda. The NuBus was later incorporated in Lisp products by Texas Instruments (Explorer), and used as the main expansion bus by Apple Computer and a variant called NeXTBus was developed by NeXT. It is no longer widely used outside the embedded market.
VMEbus (Versa Module Eurocard bus) is a computer bus standard, originally developed for the Motorola 68000 line of CPUs, but later widely used for many applications and standardized by the IEC as ANSI/IEEE 1014-1987. It is physically based on Eurocard sizes, mechanicals and connectors (DIN 41612), but uses its own signalling system, which Eurocard does not define. It was first developed in 1981 and continues to see widespread use today
