Patent ID: 7282984

Claim:
A smart card, comprising: a core block powered by an internal voltage; and an internal voltage converter (IVC) for providing the internal voltage, comprising: a first reference voltage generation circuit, which generates a first reference voltage that has a rough voltage waveform; a second reference voltage generator circuit, which generates a second reference voltage that has a stable voltage waveform, wherein the first reference voltage generation circuit consumes less power than the second reference voltage generation circuit; an analog MUX receiving an IVC stand-by identification signal, which outputs the second reference voltage when the IVC stand-by mode notification signal is in a first logic state, when an active state occurs during a normal operation state and the smart card is in a contact mode, and outputs the first reference voltage when the IVC stand-by mode notification signal is in a second logic state, when an idle state occurs during the normal operation state or the smart card is in a non-contact mode; and a voltage conversion circuit, which converts a level of an output voltage of the analog MUX and generates the internal voltage as a stable waveform, increased voltage when the IVC stand-by mode notification signal is in the first logic state, and as a rough waveform, increased voltage when the IVC stand-by mode notification signal is in the second logic state.