Who are PCMCIA?

PCMCIA (Personal Computer Memory Card International Association) is an association of nearly 500 companies sharing a computer industry background. Their aim is to set standards for non-proprietary PC Card™ technology providing expansion options for, primarily, notebook and portable computers. The very nature of portable computer systems dictates the requirement for ever smaller and lighter expansion options including memory, storage and I/O cards.

What are PCMCIA Cards™?

PCMCIA cards measure 54.0mm wide and 85.6mm deep (the approximate size of a credit card) and fall into three categories: Type I, Type II and Type III. The three categories denote the thickness of the card, and as this places a restriction on the available space for electrical / mechanical components, it also governs the ultimate application range. For example, considering the mechanical components required for a hard disk drive, this application would require a Type III card. In all other respects Type I, II and III cards are identical which means that thin cards may be used in thicker slots but thick cards may not be used in thinner slots. Cards are designed to be user-plugable devices and can be exchanged without the need to remove the system case.

Type I Card (3.3mm thick)

Common usage:

RAM Memory Flash Memory One-Time Programmable Memory EEPROM

Type II Card (5.0mm thick)

Common usage:

Memory Enhancement Data / Fax Modem LAN & Host Communications

Type III Card (10.5mm thick)

Common usage:

Memory Enhancement Data / Fax Modem LAN & Host Communications Removable Hard Disk Drives Radio Communications

PCMCIA Card Features

Socket Service software at the system BIOS level acts as an interface between other software and the underlying hardware. It identifies the number of physical card sockets provided in the system and reports the insertion and removal of cards while the machine is running. Power and ground contacts on the card are the longest connectors on the physical interface to ensure data integrity when devices are hot plugged. For example, it is possible to down load a file into system memory via a modem, exchange the communications card for a hard disk card and save the data without powering the system down. Each PC Card™ contains information describing its characteristics and capabilities. This is used by the system software to correctly configure the card for the host system.

PCMCIA Standards

PCMCIA provides a definition of the interface between the card and socket fitted to the host system.