Patent ID: 6118320
Filing Date: 2000-09-12
Classification: G06K

Abstract:
A clock input circuit provided in a portable information medium, wherein said clock input circuit receives an input signal via an antenna of said portable information medium and generates a clock signal based on said input signal and wherein said clock input circuit, comprises:an attenuator operably connected to said antenna, wherein said attenuator receives said input signal and outputs at least one attenuated signal;a control signal generator operably connected to said antenna, wherein said control signal generator inputs said input signal and generates at least one control signal based on an amplitude of said input signal;a selector circuit which is operably connected to said attenuator and to said control signal generator, wherein said selector circuit inputs said at least one attenuated signal and creates an output signal based on said at least one attenuated signal and said at least one control signal; anda clock signal processor which is operably coupled to said selector circuit, wherein said clock signal processor inputs said output signal and generates said clock signal based on said output signal.