摘要 |
A smart card capable of adjusting voltages supplied from an external device. In the smart card, a voltage detector detects levels of the voltages supplied from the external device and generates enable signals, if the detected levels are lower than a predetermined level. A voltage controller converts levels of the voltages supplied from the external device into levels of operating voltages of the smart card, in response to the enable signals. A logic level converter converts logic levels of signals received from the external device into logic levels of the smart card, based on a voltage difference between the voltages from the external device and the converted operating voltages. <IMAGE> |