Patent ID: 8680714
Filing Date: 2014-03-25
Classification: G05F,G06K,H02J

Abstract:
1. A smart card comprising: an internal voltage generator configured to generate a first internal voltage and a second internal voltage based on an input voltage, a level of the second internal voltage being lower than a level of the first internal voltage; a clock generator configured to receive the first internal voltage and the second internal voltage to generate a clock signal, the clock generator configured to change a frequency of the clock signal according to the level of the first internal voltage; and an internal circuit configured to operate based on the clock signal and the second internal voltage, wherein the clock generator includes, a control voltage generating unit configured to provide a control voltage based on the first internal voltage, a level of the control voltage being lower than the level of the first internal voltage, a first internal signal generating unit configured to provide a first internal signal based on the second internal voltage and the control voltage, a level of the first internal signal having the level of the second internal voltage during a first half-period of the clock signal in response to the clock signal, a second internal signal generating unit configured to provide a second internal signal based on the second internal voltage and the control voltage, a level of the second internal signal having the level of the second internal voltage during a second half-period of the clock signal in response to an inverted clock signal, the inverted clock signal having a phase opposite to a phase of the clock signal, and a clock generating unit configured to generate the clock signal and the inverted clock signal in response to the first internal signal and the second internal signal.