Eurocard is a European standard format for

printed circuit board A printed circuit board (PCB; also printed wiring board or PWB) is a medium used in Electrical engineering, electrical and electronic engineering to connect electronic components to one another in a controlled manner. It takes the form of a L ...

(PCB) cards that can be plugged together into a standard chassis which, in turn, can be mounted in a

19-inch rack A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is wide. The 19 inch dimension includes the edges or "ears" that protrude from each side of the equ ...

. The chassis consists of a series of slotted card guides on the top and bottom, into which the cards are slid so they stand on end, like books on a shelf. At the spine of each card is one or more connectors which plug into mating connectors on a backplane that closes the rear of the chassis.

Dimensions

As the cards are assumed to be installed in a vertical orientation, the usual meanings of height and width are transposed: A card might be 233.35 mm "high", but only 20 mm "wide". Height is measured in

rack unit A rack unit (abbreviated U or RU) is a unit of measure defined as . It is most frequently used as a measurement of the overall height of 19-inch and 23-inch rack frames, as well as the height of equipment that mounts in these frames, whereby th ...

s, "U", with 1 U being . This dimension refers to the subrack in which the card is to be mounted, rather than the card itself. A single card is 100 mm high. Taller cards add a 133.35 mm, so that a double height card is 233.35 mm high and a triple 366.7 mm high. Enclosure heights are multiples of 3U, with the cards always shorter than the enclosure. Two common heights are 3U (a 100 mm card in a subrack) and 6U (a 233.35 mm card in a high subrack). As two 3U cards are shorter than a 6U card (by 33.35 mm), it is possible to install two 3U cards in one slot of a 6U subrack, with a mid-height structure for proper support. Card widths are specified in

horizontal pitch Horizontal pitch (HP) is a unit of length defined by the Eurocard printed circuit board standard used to measure the horizontal width of rack mounted electronic equipment, similar to the rack unit (U) used to measure vertical heights of rack mount ...

units "HP", with 1 HP being . Card depths start at and increase in increments. The most common today is , but standard hardware is available for depths of , , , , , and . {, cellspacing="0" cellpadding="5px" border="1px", , - , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , height="133px" valign="top", ↑
366.7
Triple-height
(9U) subrack , rowspan="3", ↑
board
height
+0/-0.3 , - , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , height="133px" valign="top", ↑
233.35
Double-height
(6U) subrack , - , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , style="background-color:#32CD32", , height="100px" valign="top", ↑
100
Single-height
(3U) subrack , - , width="60px", ←
400 , width="60px", ←
340 , width="60px", ←
280 , width="60px", ←
220 , width="60px", ←
160 , width="100px", ←
100 , rowspan="2" colspan="2" align="center", Valid Eurocard sizes.
Dimensions in mm.
Connectors on the right. , - , colspan="6" align="center", ← board depth +0/-0.3

Standards and architecture

The Eurocard mechanical architecture was defined originally under IEC-60297-3. Today, the most widely recognized standards for this mechanical structure are

IEEE The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operation ...

1101.1, IEEE 1101.10 (also known commonly as "dot ten") and IEEE 1101.11. IEEE 1101.10 covers the additional mechanical and

electromagnetic interference Electromagnetic interference (EMI), also called radio-frequency interference (RFI) when in the radio frequency spectrum, is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electros ...

features required for

VITA Vita or VITA (plural vitae) is Latin for "life", and may refer to: * ''Vita'', the usual start to the title of a biography in Latin, by which (in a known context) the work is often referred to; frequently of a saint, then called hagiography * Vit ...

1.1-1997(R2002), which is the VME64 Extensions standard, as well as

PICMG PICMG, or PCI Industrial Computer Manufacturers Group, is a consortium of over 140 companies. Founded in 1994, the group was originally formed to adapt PCI technology for use in high-performance telecommunications, military, and industrial comp ...

2.0 (R3.0), which is the

CompactPCI CompactPCI is a computer bus interconnect for industrial computers, combining a Eurocard-type connector and PCI signaling and protocols. Boards are standardized to 3 U or 6U sizes, and are typically interconnected via a passive backplane. The co ...

specification. The IEEE 1101.11 standard covers rear plug-in units that are also called rear transition modules or RTMs. The Eurocard is a mechanical system and does not define the specific connector to be used or the signals that are assigned to connector contacts. The connector systems that are commonly used with Eurocard architectures include the original

DIN 41612 DIN 41612 was a DIN standard for electrical connectors that are widely used in rack based electrical systems. Standardisation of the connectors is a pre-requisite for open systems, where users expect components from different suppliers to operat ...

connector that is also standardized as IEC 60603.2. This is the connector that is used for the

VMEbus VMEbus (Versa Module Europa or 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. I ...

standard, which was IEEE 1014. The connector known as the 5-row DIN, which is used for the VME64 Extensions standard is IEC 61076-4-113. The VME64 Extension architecture defined by VITA 1.1-1997 (R2002). Another popular computer architecture that utilizes the 6U-160 Eurocard is

and

CompactPCI Express CompactPCI is a computer bus interconnect for industrial computers, combining a Eurocard-type connector and PCI signaling and protocols. Boards are standardized to 3 U or 6U sizes, and are typically interconnected via a passive backplane. The ...

. These are defined by PICMG 2.0R3 and PICMG Exp0 R1 respectively. Other computer architectures that utilize the Eurocard system are

VME eXtensions for Instrumentation VME eXtensions for instrumentation bus (VXI bus) refers to standards for automated test based upon VMEbus. VXI defines additional bus lines for timing and triggering as well as mechanical requirements and standard protocols for configuration, me ...

(VXI),

PCI eXtensions for Instrumentation PCI eXtensions for Instrumentation (PXI) is one of several modular electronic instrumentation platforms in current use. These platforms are used as a basis for building electronic test equipment, automation systems, and modular laboratory instru ...

(PXI), and

PXI Express PCI eXtensions for Instrumentation (PXI) is one of several modular electronic instrumentation platforms in current use. These platforms are used as a basis for building electronic test equipment, automation systems, and modular laboratory instru ...

. A computer architecture that used the 6U-220 Eurocard format was Multibus-II, which was IEEE 1296. Because the Eurocard system provided for so many modular card sizes and because connector manufacturers have continued to create new connectors that are compatible with this system, it is a popular mechanical standard that is also used for innumerable "one-off" applications. Conduction-cooled Eurocards are used in military and aerospace applications. They are defined by the IEEE 1101.2-1992 (2001) standard. The Eurocard standard is also the basis of the "

Eurorack Eurorack is a modular synthesizer format originally specified in 1995 by Doepfer Musikelektronik. It has since grown in popularity, and as of 2022 has become a dominant hardware modular synthesizer format, with over 15,000 modules available from ...

" format for modular electronic music synthesizers, popularized by

Doepfer Doepfer Musikelektronik GmbH is a German manufacturer of audio hardware, mostly synthesizer modules (modular synthesizer), based in Gräfelfing, Upper Bavaria and founded by Dieter Döpfer. The product range covers analog modular systems, MIDI con ...

and other manufacturers.

Dimensions

Standards and architecture

See also