Abstract: An apparatus for inductive temperature sensing comprises a coil configuration, a target, and an impedance measurement circuit. The target has a non-zero conductivity and susceptibility and the impedance measurement circuit measures the apparent inductance of the coil configuration at a measurement frequency close to the crossover frequency to provide an indication of temperature of the target.

Abstract: A passive radio frequency identification (RFID) reader is configured to dynamically vary the Q factor of its resonant antenna coil circuit in order to optimize its performance under different conditions. This RFID reader suitably provides optimal performance for both transponder reading and transponder writing operations, rather than being designed for optimal performance for only one operation or the other, or some fixed compromise between them.

Abstract: [Object] To provide a power control device capable of equalizing power between storage batteries in supplying direct-current power through three wires, that is, the positive electrode wire, the neutral wire, and the negative electrode wire. The storage batteries are connected in series between the positive electrode wire and the neutral wire and between the neutral wire and the negative electrode wire.

Abstract: A transformer-less, solid-state pressure transducer assembly having significantly better characteristics than the electro-mechanical assemblies of the prior art. The pressure transducer assembly of the present invention achieves the many of the same functions as transducer assemblies of the prior art having transformers, however the pressure transducer assembly of the present invention is smaller in size and weight, cost less to manufacture, and has increased reliability.

Abstract: A method for digitally controlling the resistive output of a temperature probe is disclosed. The system is comprised of a temperature sensor, a processor and a means under the control of the processor for modifying the resistive output such as a digital potentiometer. In one embodiment, the processor reads the temperature sensor and adjusts the potentiometer based on a correlative or predictive technique so as to provide a modified output that matches that of a standard resistive temperature probe and is compatible for display on a multi-parameter monitor.

Abstract: A method for digitally controlling the resistive output of a temperature probe is disclosed. The system is comprised of a temperature sensor, a processor and a means under the control of the processor for modifying the resistive output such as a digital potentiometer. In one embodiment, the processor reads the temperature sensor and adjusts the potentiometer based on a correlative or predictive technique so as to provide a modified output that matches that of a standard resistive temperature probe and is compatible for display on a multiparameter monitor.

Abstract: Disclosed are embodiments of an improved on-chip temperature sensing circuit, based on bolometry, which provides self calibration of the on-chip temperature sensors for ideality and an associated method of sensing temperature at a specific on-chip location. The circuit comprises a temperature sensor, an identical reference sensor with a thermally coupled heater and a comparator. The comparator is adapted to receive and compare the outputs from both the temperature and reference sensors and to drive the heater with current until the outputs match. Based on the current forced into the heater, the temperature rise of the reference sensor can be calculated, which in this state, is equal to that of the temperature sensor.

Abstract: A thermal sensor providing simultaneous measurement of two diodes. A first diode and a second diode are coupled to a first current source and a second current source, respectively. The ratio of the currents provided by the two sources is accurately known. The voltage across each of the two diodes may be coupled to the input of a differential amplifier for determination of temperature. Alternatively, the first diode may be coupled to a first current source by a resistor with a known voltage drop, and the second diode may be coupled to an adjustable second current source. The current in the second diode may be adjusted until the voltage across the second diode is equal to the sum of voltage drop across the first diode and the known voltage drop across the resistor. Under the established conditions, the Diode Equation may be used to calculate a temperature.

Abstract: A thermal sensor providing simultaneous measurement of two diodes. A first diode and a second diode are coupled to a first current source and a second current source, respectively. The ratio of the currents provided by the two sources is accurately known. The voltage across each of the two diodes may be coupled to the input of a differential amplifier for determination of temperature. Alternatively, the first diode may be coupled to a first current source by a resistor with a known voltage drop, and the second diode may be coupled to an adjustable second current source. The current in the second diode may be adjusted until the voltage across the second diode is equal to the sum of voltage drop across the first diode and the known voltage drop across the resistor. Under the established conditions, the Diode Equation may be used to calculate a temperature.

Abstract: A patient temperature repeating system and a method of repeating patient temperature information from a resistive-type patient temperature sensor allow one or more medical instruments to utilize a single patient temperature sensor. In one embodiment, the patient temperature repeating system (10) includes input and output connectors (12, 14), a microprocessor (20), optical isolators (22), a coarse digital potentiometer (24) in parallel with a fine digital potentiometer (26), a current sense resistor (28), amplifiers (30A, 30B), analog-to-digital converters (32A, 32B), a filter (34), fuses (36), a non-volatile memory device (38), and a relay (40).

Abstract: A microprocessor controlled high precision electronic digital thermometer which is capable of producing highly accurate temperature readings while using relatively inexpensive components. The digital thermometer of the invention uses a thermistor probe to obtain highly accurate temperature measurements which may be obtained over an extended temperature range. The digital thermometer of the invention is constructed in a manner such that by using relatively inexpensive stable resistors in a bridge, highly accurate temperature readings may be obtained by rapid calibration and recalibration of the bridge in order to obviate the need for expensive precision resistors in the bridge circuit itself.

Abstract: A temperature monitoring system provides a first, coarse temperature output signal, and a second, fine temperature output signal based on the first, coarse output signal. The fine output signal has a higher resolution than the coarse output signal, and permits fine temperature control of an apparatus at a variable control output. The fine output signal is automatically calibrated upon switching from the coarse to the fine signal.

Abstract: There is disclosed a fast responding temperature transducer circuit which provides an accurate steady-state output representing temperature in short periods of time. The circuit includes a temperature sensor which is sampled during alternate periods of time so that during one period, the temperature sensor provides a signal representing temperature, and during the alternate periods, the sensor output is shorted to prevent heat dissipation within the temperature sensor. The system may be used to achieve steady-state outputs in environments requiring fast response without a loss of accuracy and operable over wide temperature ranges.

Abstract: A calibration system for a temperature sensing probe in an electronic thermometer, including: a reference temperature element having a characteristic that varies as a function of temperature; a reference temperature sensing circuit, responsive to the reference element, for providing a reference signal representative of the temperature sensed by the reference element; a probe temperature sensing circuit responsive to the probe for providing a probe signal representative of the temperature sensed by the probe; means for releasably interconnecting the probe and the probe temperature sensing circuit; and comparator means for comparing the probe signal representative of the temperature sensed by the probe and the reference signal representative of the temperature sensed by the reference element; the probe temperature sensing circuit being responsive to the comparator means for adjusting the probe signal representative of the temperature sensed by the probe to match the reference signal representative of the temper