Power switch for external module adapted to interface with a portable information handling system

摘要

The application of external power to an external module connected to a portable information handling system enables the card detection signal to be asserted low, thereby allowing the personal digital assistant to detect and activate the external module. When external power is disconnected from the external module, the card detect signals turn off, thereby deactivating the external module and electrically disconnecting the external module from the personal digital assistant. Substantially all of the power for the external module is provided independently from the internal power supply of the portable information handling system.