Memory cards capable of operating with more than one power supply voltage

摘要

A memory card including a DRAM integrated circuit that operates at 3.3 V is designed to be used with an information processing device that provides the memory card with a power supply voltage of 3.3 V or 5 V. The memory card includes a power supply voltage control circuit for producing a voltage of 3.3 V from the power supply voltage provided by the information processing device and an input/output buffer disposed between the information processing device and the DRAM integrated circuit which receives the voltage of 3.3 V from the power supply voltage control circuit and converts the voltages of the signals from either device so that they can properly receive and process the signals therebetween.