Abstract: A memory card system, and a method of transmitting background information, in which the memory card system includes a host generating a background command; and a memory card providing the host with background information on whether the memory card supports a background operation, in response to the background command. Because the memory card system performs the background operation during an idle period, an operation of the memory card to be performed later can be prepared and an actual time for an operation such as read and write of the memory card can be reduced, so that performance of the memory card is considerably improved.

Abstract: A memory card system and method of transmitting lifetime information thereof includes a host generating a lifetime information command, and a memory card including a memory to store data provided from the host, the memory card providing the host with lifetime information of the memory in response to the lifetime information command of the host.

Abstract: A contactless card including an antenna coil, a resonant capacitor coupled between both end terminals of the antenna, a plurality of capacitors coupled in parallel with the terminals of the antenna correspondingly through switches, a shunt transistor coupled between the terminals of the antenna, forming a bypassing current path, a rectifier coupled between the terminals of the antenna, generating a DC voltage, and a control circuit sensing the DC voltage and controlling a gate voltage of the shunt transistor and on/off conditions of the switches in accordance with the sensed DC voltage.