Patent ID: 6952560
Filing Date: 2005-10-04
Classification: G06K

Abstract:
1. A tuned antenna resonant circuit of a passive transponder, the operating energy of which is capacitively drawn from a high-frequency electromagnetic carrier field, and which has a semiconductor body with an integrated circuit (IS) with a signal part (ST) with reference potential connection, which has an antenna arrangement arranged on a substrate, the antenna arrangement is linked to the integrated circuit (IS) via a contact surface (BP) connected on the semiconductor body, in which the antenna arrangement (AN) forms a serial resonant circuit with an input capacitor of the integrated circuit (IS), wherein parasitic, capacitive and resistive parts, which form a current path between the contact surface (BP) and the reference potential, are reduced in order to raise the quality of the antenna resonant circuit, wherein the current path is divided into a first current path and a second current path at at least one point by means of a series connection and a parallel connection of the capacitive and resistive parts, and wherein the parallel connection of a low capacitance of low quality and a low capacitance of high quality is connected in series to a first capacitance of high quality.