G06K 19/071

Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards {also with resonating or responding marks without active components} with integrated circuit chips {at least one of the integrated circuit chips comprising an arrangement for power management the arrangement being capable of collecting energy from external energy sources, e.g. thermocouples, vibration, electromagnetic radiation the source being electromagnetic or magnetic the source being a field other than an interrogation field, e.g. WLAN, cellular phone network}