Data carrier with sensor

1. A circuit for communicating an output signal representative of an environmental parameter, the circuit arrangement comprising:

a first connection pad and a second connection pad arranged to receive a radio frequency signal that communicates data and provides power to the circuit arrangement, the first connection pad arranged to receive a sensor signal that represents the environmental parameter, and the first connection pad and the second connection pad coupling the circuit arrangement for simultaneously receiving the radio frequency signal and the sensor signal;

a measurement circuit coupled to the first and second connection pads, the measurement circuit arranged to receive the sensor signal via the first connection pad;

a converter circuit coupled to the measurement circuit and arranged to convert a signal output by the measurement circuit into the output signal; and

a shorting circuit coupled to the measurement circuit and configured and arranged to short-circuit the radio frequency signals between the connection pads during a sensing period in which the measurement circuit measures the sensor signal.

2. The circuit of claim 1 , further comprising a voltage supply circuit coupled to the connection pads, measurement circuit, converter circuit, and shorting circuit, the voltage supply circuit configured and arranged to power the circuit arrangement, and to store power for powering the circuit arrangement while the radio frequency signals are short-circuited.

3. The circuit of claim 2 , wherein the voltage supply circuit includes a Schottky diode and a buffer capacitor coupled in series between the connection pads.

4. The circuit of claim 1 , further comprising a timing stage circuit coupled to the measurement circuit, wherein:

the measurement circuit includes a capacitor that is connected to the first connection pad and a first switching transistor that is connected in series with the capacitor and connected to the second connection pad; and

the timing stage circuit is configured and arranged to provide a conductivity control signal to the first switching transistor for controlling a conductivity mode of the first switching transistor.

5. The circuit of claim 4 , wherein the timing stage circuit is further configured and arranged to generate and provide the conductivity control signal during a measurement time period t, such that the first switching transistor is driven into its conducting mode during the measurement time period t.

6. The circuit of claim 5 , wherein the timing stage circuit is further configured and arranged to provide the conductivity signal between a lower time period limit t 1 , defined by a charging time constant of the capacitor, and an upper time period limit t 0 , defined by a power consumption determined by electrical characteristics of the circuit.

7. A circuit for a data carrier, the data carrier including a sensor circuit that is configured to provide a sensor signal representative of an environment parameter and a communication circuit that is configured to provide contactless communication with an interrogator station, the circuit comprising:

a first connection pad and a second connection pad arranged to connect the circuit to the communication circuit for communicating with the interrogator station and for receiving radio frequency power from the interrogator station, and arranged to connect the circuit to the sensor circuit for receiving the sensor signal;

a sensor signal processor including a measurement circuit coupled to the first and second connection pads, the measurement circuit arranged to receive the sensor signal via the first connection pad, and the processor configured and arranged to process the received sensor signal, and in response to a signal from the measurement circuit provide an output to the interrogator station via the first and second connection pads;

wherein the first connection pad and the second connection pad couple the circuit for simultaneously communicating with both the communication circuit and the sensor circuit; and

a shorting circuit coupled to the measurement circuit and configured and arranged to short-circuit radio frequency signals coupled to the connection pads from the communication circuit, during a sensing period in which the signal processor is receiving a signal from the sensor circuit, via the respective pads.

8. The circuit of claim 7 , wherein:

the measurement circuit includes a capacitor that is connected to the first connection pad and a first switching transistor that is connected in series with the capacitor and connected to the second connection pad, and

the sensor signal processor is configured and arranged to provide a conductivity control signal to a control electrode of the first switching transistor for controlling a conductivity mode of the first switching transistor.

9. The circuit of claim 8 , wherein the sensor signal processor includes a timing stage configured and arranged generate and provide the conductivity control signal during a measurement time period t, such that the first switching transistor is driven into its conducting mode during the measurement time period t.

10. The circuit of claim 9 , wherein the timing stage is configured and arranged to provide the conductivity signal between a lower time period limit t 1 , defined by a charging time constant of the capacitor, and an upper time period limit t 0 , defined by a power consumption determined by electrical characteristics of the circuit.

11. A circuit arrangement for communicating an output signal representative of an environmental parameter, the circuit arrangement comprising:

means, including a first connection pad and a second connection pad, for receiving a radio frequency signal that communicates data and provides power to the circuit arrangement, the first connection pad arranged to receive a sensor signal that represents the environmental parameter, and the first connection pad and the second connection pad coupling the circuit arrangement for simultaneously receiving the radio frequency signal and the sensor signal;

means, including a measurement circuit coupled to the first and second connection pads, for receiving the sensor signal via the first connection pad;

means for converting a signal output by the measurement circuit into the output signal; and

a shorting means, coupled to the measurement circuit, for short-circuiting the radio frequency signals between the connection pads during a sensing period in which the measurement circuit measures the sensor signal.

12. A method for communicating an output signal representative of an environmental parameter, the method comprising:

by using a first connection pad and a second connection pad, receiving a radio frequency signal that communicates data and provides power to the circuit arrangement, the first connection pad arranged to receive a sensor signal that represents the environmental parameter, and the first connection pad and the second connection pad coupling the circuit arrangement for simultaneously receiving the radio frequency signal and the sensor signal;

by using a measurement circuit coupled to the first and second connection pads, receiving the sensor signal via the first connection pad;

converting a signal output by the measurement circuit into the output signal; and

short-circuiting the radio frequency signals between the connection pads during a sensing period in which the measurement circuit measures the sensor signal.