Abstract: A transponder power supply for providing a supply current based on an antenna input signal. The transponder power supply comprises an emergency circuit comprising a charging circuit, an emergency capacitor, and an output stage. The charging circuit is configured to charge the emergency capacitor based on the antenna input signal to a maximum voltage which is higher than a voltage of the antenna input signal. The output stage is configured to provide a contribution to the supply current using a charge of the emergency capacitor.

Abstract: A voltage regulation and modulation circuit of a contactless device, including an adjustable impedance circuit configured to maintain an amplitude of an input voltage to be less than an amplitude of a reference voltage; a current buffer circuit coupled between the adjustable impedance circuit and a load, and configured to buffer a supply current, which is output from the adjustable impedance circuit, to the load; and a parallel regulator coupled to an output of the current buffer circuit, and configured to maintain a constant supply voltage at the load.

Abstract: A transponder power supply for providing a supply current based on an antenna input signal. The transponder power supply comprises an emergency circuit comprising a charging circuit, an emergency capacitor, and an output stage. The charging circuit is configured to charge the emergency capacitor based on the antenna input signal to a maximum voltage which is higher than a voltage of the antenna input signal. The output stage is configured to provide a contribution to the supply current using a charge of the emergency capacitor.

Abstract: A power supply input selection circuit for selecting one of a plurality of power supply inputs to supply power to a driven circuit. The power supply input selection circuit includes a power supply input switching circuit configured to provide operating power to the driven circuit by routing a selected one of the power supply inputs to the driven circuit as a function of power supply selection information; and a logic circuit configured to change the power supply selection information if a default power mode does not match a desired power mode, the logic circuit being further configured to reset the power supply input selection circuit after changing the power supply selection information, the power supply selection information being maintained during the reset, in which the power supply input switching circuit selects a desired one of the power supply inputs after the logic circuit resets the power supply input selection circuit.

Abstract: A transponder power supply for providing a supply current based on an antenna input signal. The transponder power supply comprises an emergency circuit comprising a charging circuit, an emergency capacitor, and an output stage. The charging circuit is configured to charge the emergency capacitor based on the antenna input signal to a maximum voltage which is higher than a voltage of the antenna input signal. The output stage is configured to provide a contribution to the supply current using a charge of the emergency capacitor.

Abstract: An RFID transponder having an adjustable response field strength including a determination circuit formed to determine a quantity which is derivable from a field strength of an electromagnetic field prevailing at the location of the RFID transponder, a comparator formed to compare the determined quantity derived from the field strength with a threshold value, wherein the threshold value is based on the adjustable response field strength, which is higher than the minimum field strength required for the operation of the RFID transponder, and a deactivator formed to deactivate a functionality of the RFID transponder if the derived quantity falls below the threshold value.

Abstract: An RFID transponder having an adjustable response field strength including a determination circuit formed to determine a quantity which is derivable from a field strength of an electromagnetic field prevailing at the location of the RFID transponder, a comparator formed to compare the determined quantity derived from the field strength with a threshold value, wherein the threshold value is based on the adjustable response field strength, which is higher than the minimum field strength required for the operation of the RFID transponder, and a deactivator formed to deactivate a functionality of the RFID transponder if the derived quantity falls below the threshold value.

Abstract: A transponder power supply for providing a supply current based on an antenna input signal. The transponder power supply comprises an emergency circuit comprising a charging circuit, an emergency capacitor, and an output stage. The charging circuit is configured to charge the emergency capacitor based on the antenna input signal to a maximum voltage which is higher than a voltage of the antenna input signal. The output stage is configured to provide a contribution to the supply current using a charge of the emergency capacitor.

Abstract: A voltage regulation and modulation circuit of a contactless device, including an adjustable impedance circuit configured to maintain an amplitude of an input voltage to be less than an amplitude of a reference voltage; a current buffer circuit coupled between the adjustable impedance circuit and a load, and configured to buffer a supply current, which is output from the adjustable impedance circuit, to the load; and a parallel regulator coupled to an output of the current buffer circuit, and configured to maintain a constant supply voltage at the load.

Abstract: A power supply input selection circuit for selecting one of a plurality of power supply inputs to supply power to a driven circuit. The power supply input selection circuit includes a power supply input switching circuit configured to provide operating power to the driven circuit by routing a selected one of the power supply inputs to the driven circuit as a function of power supply selection information; and a logic circuit configured to change the power supply selection information if a default power mode does not match a desired power mode, the logic circuit being further configured to reset the power supply input selection circuit after changing the power supply selection information, the power supply selection information being maintained during the reset, in which the power supply input switching circuit selects a desired one of the power supply inputs after the logic circuit resets the power supply input selection circuit.

Abstract: A voltage supply circuit has a first supply voltage input connected to a first comparator and to a first voltage regulator, the first comparator controlling the first voltage regulator. A second supply voltage input is connected to a second comparator and to a second voltage regulator, the second comparator controlling the second voltage regulator. A supply voltage output is connected to the outputs of the two voltage regulators and is fed back to the two comparators.

Abstract: A selection circuit having a comparator with comparator inputs connected to first and second voltage inputs), respectively, and a comparator output connected to a control input of a first controllable switch and an inverter. The selection circuit also has a second controllable switch having a second control input connected to the inverter. The first voltage input is connectable to a selection circuit output by the first controllable switch and the second voltage input is connectable to the selection circuit output by the second controllable switch. The inverter has a power supply connector connected to the first voltage input and the comparator has a power supply connector connected to the second voltage input.

Abstract: Circuit for generating a supply voltage having a voltage input connected to a voltage regulator that generates a first supply voltage and to a low-noise voltage regulator that generates a low-noise supply voltage. A control unit determines which of the two supply voltages is switched to a supply voltage output of the circuit.

Abstract: Device for supplying a data transfer unit with energy, having an energy supply input via which the energy can be fed into the data transfer unit, and a decoupling unit for coupling and decoupling the energy supply input to and from the data transfer unit, wherein the decoupling unit decouples when a supply voltage for the data transfer unit leaves a tolerance range.

Abstract: Circuit arrangement for voltage regulation having a differential amplifier having first and second inputs and first and second outputs, wherein a reference voltage is applied to the first input and a voltage to be regulated is applied to the second input. A charge pump is connected to the first output of the differential amplifier. A current mirror is connected to the second output of the differential amplifier. A transistor, which influences the voltage to be regulated, has its control input connected to the current mirror and the charge pump.