POWER SUPPLY METHOD AND ELECTRONIC CARD USING THE SAME

Provided is a power supply method for efficient operation of electronic cards and an electronic card using the same, and the power supply method may include the steps of: charging a charging unit through the DC power supplied from a rectification unit; enabling, when a constant voltage enable signal is applied, a system constant voltage unit if a predefined condition is satisfied; and supplying power to a system unit when the system constant voltage unit is enabled.