Patent ID: 7746231
Filing Date: 2010-06-29
Classification: G06K

Abstract:
1. A detector circuit for a receive path of a transponder, the detector circuit comprising: an input for receiving a signal derived from a high frequency electromagnetic carrier signal; a circuit component for detecting and analyzing a signal voltage derived from said received signal, the circuit component including, following said input, a signal capacitor across which the signal voltage which is dependent on the field strength of the carrier signal drops, and an analysis circuit following the signal capacitor for analyzing the signal voltage; and a circuit arrangement for load regulation that draws a discharge current from the circuit component in the event that a magnitude of the signal voltage exceeds a predetermined threshold wherein, when said signal voltage is greater than said predetermined threshold, said circuit arrangement provides substantially all of a required discharge current for reproducing the signal voltage and when said signal voltage is less than said predetermined threshold substantially all of said required discharge current for reproducing the signal voltage is provided by said circuit component.