CompactPCI is a standard PICMG for high-end systems in 19 - inch technology with passive backplane for high requirements in terms of performance, robustness and reliability. CompactPCI can be flexibly constructed as a multi-computer system and is based on the Eurocard format.

The connection to the backplane via five-row gas-tight and shielded connectors. In addition to the PCI bus signals (110 pins on connector J1) are on the J2 connector 110 pins for 64- bit PCI expansion and reserved system control signals or user I / O and double Eurocards ( 6 U ) on the connectors J3, J4 and 315 J5 pins for user I / O provided. In CompactPCI provides that cards can be replaced during operation ( "hot swapping" ). This requires both mechanical (different pin lengths ), electrical ( no interference on the backplane) and programming measures for controlled activation and deactivation of drivers.

CompactPCI backplanes can contain up to eight slots, of which the so-called system slot for the host CPU card is provided with the bus arbiter. A PCI-to- PCI bridge, the number of cards can be increased further.

The electrical specifications are based on the standard PCI (Peripheral Component Interconnect), but are partly limited by, for example, all PCI signals may only be loaded with a load unit (except for the system slot ). A voltage supply of 5 V, 3.3 V, 12 V and -12 V are provided. With a locking mechanism prevents cards in 3.3V technology 5V slots can be inserted or vice versa.

CompactPCI is abbreviated in slang as " cPCI " or " CPCI ". The PICMG has distanced himself from these designations, however. You are no longer officially used.