Compact PCI Bus

Compact Peripheral Component Interface
cPCI Bus

[cPCI Description] [cPCI Interface ICs]
[cPCI Connectors] [cPCI PinOut] [OnLine Standards]
[cPCI COTS Cards] [cPCI Chassis] [cPCI Backplanes] [PCI page]

Compact PCI Description

A board format specification that defines both the mechanical and electrical characteristics.

cPCI [Compact Peripheral Component Interface] is electrically identical to the PCI specification, except it uses the Euro (VME) card 3U/6U format with 2mm connectors. The cPCI bus uses 8, 16, 32, or 64 bit transfers at up to 264MBps. 64 bit PCI transfers may be used in either 3U or 6U size cards. 6U boards contain additional pins for user defined I/O.
3U card dimensions are 100mm x 160mm x 1.6mm thick, 6U card dimensions are 233.35mm x 160mm x 1.6mm thick.

The PCI spec defines the Electrical requirements for the interface. No bus terminations are specified, the bus relies on signal reflection to achieve level threshold. The first version of the PCI bus ran at 33MHz with a 32 bit bus (133MBps), then added 64 bits at 33MHz (266MBps). The current version runs at 66MHz with a 64 bit bus (532Mbps). The PCI bus operates either synchronously or asynchronously with the "Mother Board" bus rate. While operating asynchronously the bus will operate at any frequency from 66MHz down to (and including) 0Hz. Flow control is added to allow the bus to operate with slower devices on the bus, allowing the bus to operate at their speed. PCI is an unterminated bus, the signals relay on signal reflections to attain their final value. The PCI specification has been port-ed to a number of other form factors.

Addition features of cPCI include; live insertion support (Hot-Swap), supports two independent buses on the backplane (on different connectors), and soon Infiniband, Ethernet, and Star Fabric support (Switched Fabric based systems).

PXI defines cPCI for Instrumentation adding additional enhancements, with the same form factor as cPCI. PXI adds additional signals and chassis requirements just like VXI adds to VME. Unlike VXI, PXI does not require that the card be enclosed in a metal shield.

The newest version in the cPCI form factor is called cPCIe and trades in the PCI bus for the PCIe bus.

{cPCI Bus Index}

Compact PCI Online Standards Info

PICMG 2.0 Rev 3.0 CompactPCI Core Specification; See also the PCI Page
PICMG 2.1 Rev2.0 CompactPCI Hot Swap
PICMG 2.2 Rev1.0 VME64x on CompactPCI [VME64x bus on the P4/P5 connectors]
PICMG 2.3 Rev1.0 PMC on CompactPCI
PICMG 2.4 Rev1.0 IP on CompactPCI
PICMG 2.5 Rev1.0 CompactPCI Computer Telephony
PICMG 2.7 Rev1.0 6U CompactPCI Dual System Slot Specification
PICMG 2.9 Rev1.0 CompactPCI System Management
PICMG 2.10 Rev1.0 Keying of CompactPCI Boards and Backplanes
PICMG 2.11 Rev1.0 CompactPCI Power Interface
PICMG 2.12 Rev2.0 Hot Swap Infrastructure Interface
PICMG 2.14 Rev1.0 CompactPCI Multicomputing Specification
PICMG 2.15 Rev1.0 PCI Telecom Mezzanine/Carrier Card [H.110 [TDM bus] Computer Telephony]
PICMG 2.16 Rev1.0 CompactPCI Packet Switching Backplane Specification [cPSB] (GigaBridge, Ethernet)
PICMG 2.17 Rev1.0 CompactPCI StarFabric Specification
PICMG 2.20 Rev1.0 CompactPCI Serial Mesh Backplane Specification
PXI Rev 1.0 PXI; PCI eXtensions for Instrumentation

Compact PCI Industrial Computer Manufacturers Group {PICMG} .. IEEE {Institute of Electrical and Electronic Engineers,}

Card dimensions [size] / Form Factor

cPCI Card size description, and Board Dimensions
Card Formats

{cPCI Bus Index}

Compact PCI Bus Pin-Out

cPCI P1/J1 Pinout {2mm style}

cPCI P2/J2 Pinout {2mm style}

Pinouts for the other connectors found on a 6U card are user defined.
While the pinout for a 3U card is fully defined by the links above. The 3U size card only uses the P1/P2 connectors.

{cPCI Bus Index}

Compact PCI Bus Interface IC Manufacturers

Using the same specification as PCI, cPCI may use the same IC's as the PCI bus specification.
The PCI bus doesn't use Glue logic, being developed as a single chip interface bus. So signal chip solutions or ASIC parts are the only PCI chips listed below.
The +5 volt interface uses standard TTL switching levels VIH = 2v, VOH = 2.4v.
The +3.3 volt Low Voltage interface uses VIH = 1.65v, VOH = 2.97v
PCI is a CMOS bus, with no current flowing in the static state.


Altera {PCI Cores}

Analog Devices {Dual PCI Hot-Plug Controller IC}

Cirrus Logic {PCI-Disk Controller ICs}

Cypress Products.

IDT {PCI-SCI Bridge Chips}

Infineon Technologies {PC Chips-DRAM Controllers}

Intel {ISA to PC/PCI to PC/PCI to CardBus Controllers}

Marvell {PCI chip sets}

PLX Technology Inc. {PCI-to-PCI Bridge IC, PCI I/O Accelerator ICs}

QLogic {PCI-SBus devices}

QuickLogic {PCI System/Bus Master, PCI Bus Target, PCI-to-PCI Bridge ICs}

Texas Instruments 'TI' {Bridge ICs-Controllers}

Tundra Semiconductor Corp. {PCI bridges}

Xilinx {FPGA Core}

All other types IC Manufacturers

{cPCI Bus Index}

cPCI Bus Connector Manufacturers (2mm)

cPCI uses 2mm 'Hard Metric'; IEC 1076-4-101, a number of different pin arrangements. Normally the outside Ground rows (which are compression pins) 'Z' and 'F' are not counted as pins. OEM pin numbering may be by cPCI or in accordance with IEC 61076-4-101 (which is reversed). The term "Hard Metric" only means that metric dimensions are preferred ~ with-out regard to inches.

cPCI 2mm connectors mating distances [12.50mm] matches the 96 pin DIN 41612 connectors used with other EuroCard packaging [IEC 273 or IEEE 1101, 1101.10], like VMEbus. FutureBus connectors, which also use 2mm style has a mating distance of 10mm, and is not compatible with cPCI connectors.

The types below are counting signal pins (not the ground rows), as indicated on many data sheets:

Type A; 110 pins, Keyed (J1/J4),([25 rows x 5 columns] - [3 rows x 5 columns of Key])
Type B; 110 pins (J2/J5), [22 x 5]
Type B; 95 pins (J3), [19 x 5]. This is also used as P0 with VME64
Type C; 55 pins [11 x 5]
Type AB; 95, 110, or 125 pins

There are other types:
Type L; # contact cavities to accept power insert contacts
Type M; # contact cavities to accept power insert contacts/with half the connector having normal pins

cPCI Connector Location
CompactPCI Euro-Card Form Factor

The card side connector is Male (Right-Angle), the back plane side is Female (Straight).

A new cPCI connector with better shielding is called Ultra Hard Metric [UHM]



Delphi Connection Systems

DINTEK {Hard Metric Male/Female. Press Fit. A number of Tail Lengths}

ecs {2mm Hard Metric connectors}





Hirose Electric

ITT Industries

Meritec {2mm cPCI backplane cable assemblies, off the shelf product and customizable products.}


OUPIIN America Inc.

Positronic Industries {Power Module Connectors}

Tyco Electronics

Compact PCI Chassis Manufacturers (2mm)

CompactPCI [cPCI] Chassis will be between 1 and 8 slots (the maximum). Printed Wiring Boards [PWB] are spaced on 0.8 inch centers.
The chassis may accept 3U cards, or 3U and 6U cards. The chassis may have a separate card cage to handle the 3U cards.

The chassis shall provide a +5volt, +/- 12volt and a 3.3volt supply @ maximum ripple 50mV. I believe the Telcom version provides 48 volts as the system power.
The backplane is passive. The bus requires one card acting as the systems controller residing at either end of the back-plane (chassis), termed the System Slot. The remaining cards (slots) are termed the Peripheral Slots.

PXI, cPCI for Instrumentation uses the same chassis. cPCI and PXI Chassis manufacturers

In cPCI, the system slot may reside in any slot of the back plane with the other 7 slots as peripheral cards. In PXI, the left most slot is the system slot followed on the right by 7 peripheral slots. In addition, 3 other slots, with do not contain back plane connectors may reside to the left of the system slot. These additional 3 slots provide expansion (wider card) for the system card.

How to spec out an equipment chassis; Chassis Design Considerations.

{cPCI Bus Index}

Compact PCI COTs Card Manufacturers

CompactPCI [cPCI] uses the Euro Format [dimensions], see figure above.
IEEE 1101.1 Base Document for Mechanics
IEEE 1101.10 Mechanics for VME Boards and Subracks
IEEE 1101.11 Mechanics for Rear Transition Modules

CompactPCI [cPCI] cards may be either 3U {100mm x 160mm} or 6U {233 x 160mm).
The boards should be keyed to indicate either 5V or 3.3v operation.
3U card will use J1 and may use J2, 6U cards shall use J1 and may use J2 to J5.
J1 is used for 32 bit PCI, J2 is used for 64 bit PCI, J3 to J5 are used for user definable signals.

cPCI Card manufacturers and vendors, or cPCI Backplanes manufacturers

Navigation: Engineering Home > Interface Buses > Backplane Interface Standards > cPCI Board Standard.

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Modified 6/13/15
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