ABSTRACT In this paper, we present a temperature compensation method for logarithmic CMOS image sensors. As Bandgap technique, the compensation circuit generates VPTAT1 and VPTAT2 voltages to compensate temperature variation of the sensor output signal voltage (Out-AC-Signal) which we call VCTAT1 and output reference voltage (VRef−ph) which we call VCTAT2. The proposed method is divided into th...

A low-voltage temperature sensor designed for MEMS power harvesting systems is fabricated. The core of the sensor is a bandgap voltage reference circuit operating with a supply voltage in the range 1–1.5 V. The prototype was fabricated on a conventional 0.5 mm silicon-onsapphire (SOS) process. The sensor design consumes 15 mA of current at 1 V. The internal reference voltage is 550 mV. The temp...

A wireless passive high-temperature pressure sensor without evacuation channel fabricated in high-temperature co-fired ceramics (HTCC) technology is proposed. The properties of the HTCC material ensure the sensor can be applied in harsh environments. The sensor without evacuation channel can be completely gastight. The wireless data is obtained with a reader antenna by mutual inductance couplin...

This paper demonstrates a novel flow sensor with two-dimensional 360° direction sensitivity achieved with a simple structure and a novel data fusion algorithm. Four sensing elements with roundabout wires distributed in four quadrants of a circle compose the sensor probe, and work in constant temperature difference (CTD) mode as both Joule heaters and temperature detectors. The magnitude and dir...

− This paper proposes a low-cost technique to compensate for the temperature dependence of piezoresistive pressure sensors configured in a Wheatstone bridge. The sensor is treated as a resistive circuit and three equivalent resistances are measured by setting appropriately the bridge terminals. One of these equivalent resistances depends on temperature but not on pressure and, hence, it can be ...

Cerebral hyperthermia caused by perfusate temperature greater than 37 degrees C during the rewarming phase of CPB has been linked to postoperative neurologic deficits. The purpose of this study was to determine the accuracy of the coupled temperature measurement system and the CDI 500 arterial temperature sensor. Seventeen patients undergoing CPB were divided into four groups, each with a diffe...

Soil moisture sensors can help to reduce the amount of water needed for irrigation. In this paper we describe the PlantCare soil moisture sensor as a new type of heat dissipation sensor, its calibration and the correction for temperature changes. With the PlantCare sensor it is possible to measure the matric potential indirectly to monitor or control irrigation. This sensor is based on thermal ...

A compensation method for the sensitivity drift of a magnetoresistive (MR) Wheatstone bridge current sensor is proposed. The technique was carried out by placing a ruthenium temperature sensor and the MR sensor to be compensated inside a generalized impedance converter circuit (GIC). No internal modification of the sensor bridge arms is required so that the circuit is capable of compensating pr...

Iron oxide (Fe₂O₃) nanopowder was prepared by a precipitation method and then mixed with different proportions of carbon nanotubes. The composite materials were characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. A fabricated heater-type gas sensor was compared with a pure Fe₂O₃ gas sensor under the influence of acetone. The effec...

An ultra-low power embedded CMOS temperature sensor based on serially connected subthreshold MOS operation is implemented in a 0.18 m CMOS process for passive RFID food monitoring applications. Employing serially connected subthreshold MOS as sensing element enables reduced minimum supply voltage for further power reduction, which is of utmost importance in passive RFID applications. Both propo...