Abstract: A circuit arrangement having a changeover apparatus which provides a first voltage in a first state and a second voltage in a second state in order to operate a circuit, where the changeover apparatus is designed such that when changing over from the first state to the second state the voltage provided for operating the circuit changes from the first voltage to the second voltage linearly with time.

Abstract: A voltage regulator arrangement having a first voltage regulator, whose input connection is connected to the supply potential connection and whose output connection is connected to a first supply potential connection of a circuit arrangement, with the first voltage regulator supplying the circuit arrangement with a supply voltage in a rest state. A second voltage regulator is also provided, whose input connection is connected to the supply potential connection, and whose output connection is connected to a second supply potential connection of the circuit arrangement, with the second voltage regulator supplying the circuit arrangement with a supply voltage during its normal operation.

Abstract: A current-supply circuit includes a regulation transistor. The regulation transistor is formed to regulate, based on a first supply voltage present on a first supply-voltage feed line, a second supply voltage present on a second supply-voltage feed line. The regulation transistor provides a supply current to the second supply-voltage feed line. The voltage-supply circuit further includes an operating-point determiner, which is formed to determine, based on information that is a measure for the supply current, whether the regulation transistor is at a low operating point at which the supply current is below a determined current. The voltage-supply circuit further includes a preventer that is formed to prevent, starting from the low operating point, a rise of the supply current by at least a predetermined current amount from occurring within a predetermined period.

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 circuit arrangement having a voltage regulator, which is designed to generate a regulated operating voltage, and a voltage monitoring unit, which is designed to monitor the regulated operating voltage for deviations from desired values. The voltage monitoring unit has a first detector, which is designed to cause an alarm signal to be generated when the first detector detects that the regulated operating voltage is outside a first voltage interval, and a second detector, which is designed to cause an initiator to initiate countermeasures which influence the regulated operating voltage when the second detector detects that the regulated operating voltage is outside a second voltage interval, which is inside the first voltage interval.

Abstract: A circuit arrangement having a changeover apparatus which provides a first voltage in a first state and a second voltage in a second state in order to operate a circuit, where the changeover apparatus is designed such that when changing over from the first state to the second state the voltage provided for operating the circuit changes from the first voltage to the second voltage linearly with time.

Abstract: A circuit arrangement for voltage regulation having a series regulator with a regulating amplifier and a charge pump that is connected downstream of the regulating amplifier, a reference voltage unit that generates a reference voltage for the regulating amplifier, and a starter unit that generates a starter voltage in order to supply the regulating amplifier, the charge pump, and the reference voltage unit with voltage while the series regulator is being started.

Abstract: A current-supply circuit includes a regulation transistor. The regulation transistor is formed to regulate, based on a first supply voltage present on a first supply-voltage feed line, a second supply voltage present on a second supply-voltage feed line. The regulation transistor provides a supply current to the second supply-voltage feed line. The voltage-supply circuit further includes an operating-point determiner, which is formed to determine, based on information that is a measure for the supply current, whether the regulation transistor is at a low operating point at which the supply current is below a determined current. The voltage-supply circuit further includes a preventer that is formed to prevent, starting from the low operating point, a rise of the supply current by at least a predetermined current amount from occurring within a predetermined period.

Abstract: A system and method for contactless data transmission. A transponder includes a reception unit for receiving a modulated RF signal, a signal processing unit which is connected downstream of the reception unit and a unit for processing at least two differently modulated and/or coded RF signals, for providing a supply voltage and for providing a data signal produced from the modulated RF signal, and a data processing unit which can be connected to the supply voltage and to which the data signal can be supplied, and which is connected to the signal processing unit for setting the modulation type and/or coding type for the RF signals to be processed. The signal processing unit is set to the process differently modulated and/or coded RF signals in chronological order, starting from application of a supply voltage until the data processing unit identifies reception of a prescribed data signal.

Abstract: A voltage regulator having a current mirror for decoupling a partial current icluding a first NMOS transistor as a series transistor. In addition, the voltage regulator has a second NMOS transistor, which forms a current mirror with the first NMOS transistor. Furthermore, in the case of the voltage regulator, the first NMOS transistor is connected in series with a first PMOS transistor and a third transistor. The second NMOS transistor is likewise connected in series with a second PMOS transistor and a fourth transistor, the control inputs of the first and second PMOS transistors being connected to one another and the control inputs of the third and fourth transistors being connected to a control terminal for setting the magnitude of the partial current to be decoupled.

Abstract: A circuit arrangement for voltage regulation having a series regulator with a regulating amplifier and a charge pump that is connected downstream of the regulating amplifier, a reference voltage unit that generates a reference voltage for the regulating amplifier, and a starter unit that generates a starter voltage in order to supply the regulating amplifier, the charge pump, and the reference voltage unit with voltage while the series regulator is being started.

Abstract: A voltage regulator having a current mirror for decoupling a partial current icluding a first NMOS transistor as a series transistor. In addition, the voltage regulator has a second NMOS transistor, which forms a current mirror with the first NMOS transistor. Furthermore, in the case of the voltage regulator, the first NMOS transistor is connected in series with a first PMOS transistor and a third transistor. The second NMOS transistor is likewise connected in series with a second PMOS transistor and a fourth transistor, the control inputs of the first and second PMOS transistors being connected to one another and the control inputs of the third and fourth transistors being connected to a control terminal for setting the magnitude of the partial current to be decoupled.

Abstract: A circuit arrangement having a voltage regulator, which is designed to generate a regulated operating voltage, and a voltage monitoring unit, which is designed to monitor the regulated operating voltage for deviations from desired values. The voltage monitoring unit has a first detector, which is designed to cause an alarm signal to be generated when the first detector detects that the regulated operating voltage is outside a first voltage interval, and a second detector, which is designed to cause an initiator to initiate countermeasures which influence the regulated operating voltage when the second detector detects that the regulated operating voltage is outside a second voltage interval, which is inside the first voltage interval.

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.

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: 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.

Abstract: A voltage regulator arrangement having a first voltage regulator, whose input connection is connected to the supply potential connection and whose output connection is connected to a first supply potential connection of a circuit arrangement, with the first voltage regulator supplying the circuit arrangement with a supply voltage in a rest state. A second voltage regulator is also provided, whose input connection is connected to the supply potential connection, and whose output connection is connected to a second supply potential connection of the circuit arrangement, with the second voltage regulator supplying the circuit arrangement with a supply voltage during its normal operation.

Abstract: The logic gate has at least one input terminal in which a digital input signal is applied having two possible logical signal values and at least one output terminal to output an output signal having a logical signal values. Two different logical voltage levels are allocated to both possible logical signal values of the output signal and a logic circuit is provided between the input and the output terminals. The logic circuit has several switching elements, especially switching transistors, working or produced according to the logical voltage level. The logic circuit is supplied with a supply potential that exceeds the logic voltage level. The logic circuit has at least two switching elements, especially switching transistors, in the output path allocated to the output terminal.

Abstract: A method for demodulating a voltage which has been ASK modulated by changing the amplitude between a low level and a high level, in particular for use during contactless data transmission from a card reader/writer to a smart card, is described. The method is distinguished, in that, in an initialization phase, a first mean value is produced from the high voltage level and a stored partial voltage derived therefrom in order to detect a change to a low voltage level. The change to the low voltage level represents a start value and is detected by a subsequent comparison of the modulated voltage with the first mean value. In a subsequent demodulation phase, a second mean value is produced from the detected low voltage level and the high voltage level in order to demodulate the modulated voltage by comparing the modulated voltage with the second mean value.

Abstract: A method for demodulating a voltage which has been ASK modulated by changing the amplitude between a low level and a high level, in particular for use during contactless data transmission from a card reader/writer to a smart card, is described. The method is distinguished, in that, in an initialization phase, a first mean value is produced from the high voltage level and a stored partial voltage derived therefrom in order to detect a change to a low voltage level. The change to the low voltage level represents a start value and is detected by a subsequent comparison of the modulated voltage with the first mean value. In a subsequent demodulation phase, a second mean value is produced from the detected low voltage level and the high voltage level in order to demodulate the modulated voltage by comparing the modulated voltage with the second mean value.