Patent ID: 11933754
Assignee: LG ELECTRONICS INC.
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 16:
17. A sensor, comprising:
a substrate;
an antenna pattern formed in a spiral shape on the substrate and configured to receive a radio signal from an external device so as to transmit a digital signal to the external device;
a first electrode and a second electrode formed on the substrate and spaced apart from each other in parallel and configured to sense a measurement value representing a change in inputted alternating current power corresponding to a change in impedance by a sensing target material being brought into contact therewith;
a circuit wiring formed to be connected to each of the first electrode and the second electrode; and
an element bonded to the antenna pattern and the circuit wiring,
wherein the element comprises:
a communicator receiving the radio signal from the antenna pattern and supplying the digital signal to be transmitted through the antenna pattern;
a power generator generating direct current power with the radio signal; and
a controller woken up by the direct current power to convert the direct current power into alternating current power so as to supply the alternating current power to the first electrode and the second electrode, and when the sensing target material is brought into contact therewith to thereby supply the digital signal to the communicator, generating the digital signal corresponding to at least one of ion concentration representing water quality of the sensing target material or salinity of the sensing target material according to a measurement voltage corresponding to an impedance change between the first electrode and the second electrode,
wherein when the radio signal is a signal requesting measurement of the ion concentration, the controller controls the power generator so that a first driving current set by the direct current power is supplied to the first electrode and the second electrode, and when the measurement voltage satisfies a set first ion reference voltage, the controller generates the digital signal corresponding to the ion concentration calculated by applying the measurement voltage to a set first logarithmic function, and
when the measurement voltage does not satisfy the first ion reference voltage, the controller controls the power generator so that a second driving current lower than the first driving current set by the direct current power is supplied to the first electrode and the second electrode, and when the measurement voltage satisfies a second ion reference voltage, the controller generates the digital signal corresponding to the ion concentration calculated by applying the set measurement voltage to a second logarithmic function that is different from the first logarithmic function.