Voltage interface issues for PCMCIA sockets

PCMCIA expansion sockets are becoming more popular with portable equipment. The expansion sockets are also being used in desktop systems and other systems that require easy expandability. The PCMCIA specification gives a set of guidelines that form a good starting point for the design of any portable system. There are a host of other practical design issues to consider for a robust system. The main issues are switch on resistance, in-rush current, short circuit protection and switch output ringing during switching. The main features to look for in the switch matrix are easy interface to standard controllers, low enough on resistance, slowed switch rise times, and current limiting and thermal shutdown. By designing with these features the PCMCIA socket will meet the voltage requirements of all cards and will ensure a robust system