CPC G06K 19/0712 (2013.01) [G06K 19/0709 (2013.01); G06K 19/0713 (2013.01); G06K 19/0715 (2013.01); G06K 19/0718 (2013.01)] | 19 Claims |
1. An internal voltage generator of a smart card, the internal voltage generator comprising:
a mode detector configured to generate a mode signal indicating one of a contact mode and a contactless mode, the smart card configured to supply an input voltage when in direct contact with an external card reader in the contact mode, and to supply the input voltage without directly contacting the external card reader in the contactless mode;
a switched capacitor circuit configured to generate a first driving voltage and a second driving voltage based on a rectified voltage obtained by rectifying the input voltage, wherein the second driving voltage is smaller than the first driving voltage; and
a low-drop out (LDO) regulator including an error amplifier, wherein the LDO regulator is operable, responsive to the mode signal to:
in the contact mode, drive the error amplifier with the second driving voltage to generate an error voltage, and regulate the second driving voltage based on the error voltage to generate a first output voltage, and
in the contactless mode, drive the error amplifier with the first driving voltage to generate the error voltage, and regulate the second driving voltage based on the error voltage to generate the first output voltage.
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