CIRCUIT FOR REGULATING VOLTAGE, CONTACTLESS CARD, AND CONTACTLESS CARD SYSTEM COMPRISING THE SAME

摘要

PURPOSE: A voltage adjusting circuit, a contactless card including the same and a contactless card system are provided to reduce the distortion of a data signal transmitted from a card reader by locating a regulator on the back end of a rectifier circuit. CONSTITUTION: A card reader(30) supplies energy to a contactless card(50). The card reader includes a power supply(32), a logic circuit(34) and a resonance circuit(36). The resonant circuit transmits data in an electromagnetic wave shape. A voltage adjusting circuit(100) supplies a regulated output voltage to an inner logic circuit(52). An inducing circuit induces the distortion from the electromagnetic wave. A first rectifier circuit rectifies an output signal of the inducing circuit. A first regulator regulates the output signal of the first rectifier circuit. [Reference numerals] (AA) Voltage adjusting circuit