Abstract: A sensor for sensing one or more properties of a vehicle fluid has a tuning fork resonator adapted to contact the fluid. The tuning fork resonator comprises two tines and is operable to oscillate so that the two tines move in opposite phase at a frequency of less than 1 MHz while contacting the fluid to generate a resonator response indicative of one or more properties of the fluid. In another aspect, a sensor includes a substrate and a flexural resonator on the substrate and adapted to contact the fluid. Circuitry for operation of the resonator is on the substrate. The resonator is adapted to receive an input signal and to oscillate while contacting the fluid to generate a resonator response indicative of one or more properties of the fluid. One suitable application for the invention is monitoring the condition of a vehicle engine oil.

Abstract: A sensor for sensing one or more properties of a vehicle fluid has a tuning fork resonator adapted to contact the fluid. The tuning fork resonator comprises two tines and is operable to oscillate so that the two tines move in opposite phase at a frequency of less than 1 MHz while contacting the fluid to generate a resonator response indicative of one or more properties of the fluid. In another aspect, a sensor includes a substrate and a flexural resonator on the substrate and adapted to contact the fluid. Circuitry for operation of the resonator is on the substrate. The resonator is adapted to receive an input signal and to oscillate while contacting the fluid to generate a resonator response indicative of one or more properties of the fluid. One suitable application for the invention is monitoring the condition of a vehicle engine oil.

Abstract: A circuit chip is disclosed. The circuit chip includes analog-to-digital processing circuitry that is capable of interfacing with a sensor and host electronics. The analog-to-digital processing circuitry includes a frequency generator configured for providing stimulus to the sensor and signal detection circuitry that is configured for identifying amplitude data of a response signal. Further included is analog-to-digital conversion circuitry that is configured for converting the detected amplitude data into digital form. A memory that is capable of holding data characterizing the sensor is also provided. The digital form of the response signal is capable of being processed to generate fluid characteristics of fluids under-test.

Abstract: Circuitry for processing signals used to determine characteristics of a fluid under-test is provided. The circuitry includes a compensation device and integrated circuitry for interfacing with a tuning fork that is capable of being in contact with the fluid under-test and the compensation device. The compensation device is configured to differentially process a signal output of the tuning fork, and the differential processing of the compensation device is actively controlled by the integrated circuitry so as to produce a processed signal. The processed signal defines the characteristics of the fluid under-test, and the compensation device includes capacitive matching circuitry. Also provided are systems that incorporate the circuitry.

Abstract: A sensor for sensing one or more properties of a vehicle fluid has a tuning fork resonator adapted to contact the fluid. The tuning fork resonator comprises two tines and is operable to oscillate so that the two tines move in opposite phase at a frequency of less than 1 MHz while contacting the fluid to generate a resonator response indicative of one or more properties of the fluid. In another aspect, a sensor includes a substrate and a flexural resonator on the substrate and adapted to contact the fluid. Circuitry for operation of the resonator is on the substrate. The resonator is adapted to receive an input signal and to oscillate while contacting the fluid to generate a resonator response indicative of one or more properties of the fluid. One suitable application for the invention is monitoring the condition of a vehicle engine oil.

Abstract: A method for analyzing a fluid contained within a machine, comprising the steps of providing a machine including a passage for containing a fluid; placing a sensor including a mechanical resonator in the passage; operating the resonator to have a portion thereof translate through the fluid; and monitoring the response of the resonator to the fluid in the passage. A preferred sensor includes a tuning fork resonator.

Abstract: A circuit for determining characteristics of a fluid under-test is provided. The circuit includes analog-to-digital processing circuitry for interfacing with a sensor and host electronics.

Abstract: A circuit chip is disclosed. The circuit chip includes analog-to-digital processing circuitry that is capable of interfacing with a sensor and host electronics. The analog-to-digital processing circuitry includes a frequency generator configured for providing stimulus to the sensor and signal detection circuitry that is configured for identifying amplitude data of a response signal. Further included is analog-to-digital conversion circuitry that is configured for converting the detected amplitude data into digital form. A memory that is capable of holding data characterizing the sensor is also provided. The digital form of the response signal is capable of being processed to generate fluid characteristics of fluids under-test.

Abstract: A circuit for determining characteristics of a fluid under-test is provided. The circuit includes analog-to-digital processing circuitry for interfacing with a sensor and host electronics. The analog-to-digital processing circuitry includes a frequency generator for providing stimulus to the sensor and receiving a response signal from the sensor. Conditioning circuitry for reducing analog signal offsets in the response signal and signal detection circuitry for identifying amplitude data of the response signal are provided. Further provided is analog-to-digital conversion circuitry for converting the detected amplitude data into digital form. Memory for holding calibration data and approximated fluid characteristics of the fluid under-test is included in the circuitry. The digital form of the response signal is processed in conjunction with the calibration data and approximated fluid characteristics to generate fluid characteristics of the actual fluid under-test.

Abstract: A circuit for determining characteristics of a fluid under-test is provided. The circuit includes analog-to-digital processing circuitry for interfacing with a sensor and host electronics. The analog-to-digital processing circuitry includes a frequency generator for providing stimulus to the sensor and receiving a response signal from the sensor. Conditioning circuitry for reducing analog signal offsets in the response signal and signal detection circuitry for identifying amplitude data of the response signal are provided. Further provided is analog-to-digital conversion circuitry for converting the detected amplitude data into digital form. Memory for holding calibration data and approximated fluid characteristics of the fluid under-test is included in the circuitry. The digital form of the response signal is processed in conjunction with the calibration data and approximated fluid characteristics to generate fluid characteristics of the actual fluid under-test.