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Item type:Publication, A Procedure for Precise Determination and Compensation of Lead-Wire Resistance of a Two-Wire Resistance Temperature Detector(2022-06-01); ; A procedure for the precise determination and compensation of the lead-wire resistance of a resistance transducer is presented. The proposed technique is suitable for a two-wire resistance transducer, especially the resistance temperature detector (RTD). The proposed procedure provides a technique to compensate for the lead-wire resistance using a three-level pulse signal to excite the RTD via the long lead wire. In addition, the variation in the lead-wire resistance disturbed by the change in the ambient temperature can also be compensated by using the proposed technique. The determination of the lead-wire resistance from the proposed procedure requires a simple computation method performed by a digital signal processing unit. Therefore, the calculation of the RTD resistance and the lead-wire resistance can be achieved without the requirement of a high-speed digital signal processing unit. The proposed procedure is implemented on two platforms to confirm its effectiveness: the LabVIEW computer program and the microcontroller board. Experimental results show that the RTD resistance was accurately acquired, where the measured temperature varied from 0<sup>◦</sup>C to 300<sup>◦</sup>C and the lead-wire resistance varied from 0.2 Ω to 20 Ω, corresponding to the length of the 26 American wire gauge (AWG) lead wire from 1.5 m to 150 m. The average power dissipation to the RTD was very low and the self-heating of the RTD was minimized. The measurement error of the RTD resistance observed for pt100 was within ±0.98 Ω or ±0.27<sup>◦</sup>C when the lead wire of 30 m was placed in an environment with the ambient temperature varying from 30<sup>◦</sup>C to 70<sup>◦</sup>C. It is evident that the proposed procedure provided a performance that agreed with the theoretical expectation. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, System development for orange surface defect detection using image processing(2015-01-01); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Simple vector summation circuit using opamps(2011-01-01); ; This paper presents a vector summation circuit using operational amplifiers (opamps) for multiple voltage inputs. The implementation method based on the opamp supply-current sensing utilizes an inherently quadratic characteristic of the opamp class-AB output stage. The distinguishing features of the proposed implementation are simple configuration and low cost. Experimental results verifying the performances of the proposed vector summation circuit are included. © 2011 SICE. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Simple square-rooting voltage-to-frequency converter using opamps(2010-12-01); This paper presents a simple method based on commercially available operation amplifiers (Opamps) for realizing the square-rooting voltage-to-frequency converter (VFC). The realization of square-root function is provided through the use of the opamp supply-current sensing, which utilizes an inherent quadratic characteristic of the opamp class-AB output state. Experimental results verifying the performances of the proposed square-rooting VFC are included. ©ICROS. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A simple amplitude detector-based demodulator for resolver converters(2010-12-01); This paper presents a simple method based on sinusoidal-amplitude detector for realizing the resolver-signal demodulator. The proposed demodulator consists of two full-wave rectifiers, two ±unity-gain amplifiers, and two sinusoidal-amplitude detectors with control switches. Two output voltages are proportional to sine and cosine envelopes of resolver-shaft angle without low-pass filter. Experimental results demonstrating characteristic of the proposed circuit are included. ©ICROS.1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, OTA-based electronically adjustable floating positive/negative resistor(2008-12-01); 2 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Simple square-root extractor using op amps(2008-12-01) - Some of the metrics are blocked by yourconsent settings
Item type:Publication, An accurate CCII-based voltage controlled current source(2008-12-01); Kamsri, ThawatchaiIn this paper, a voltage controlled current source (VCCS) providing low distortion in output signal and wide output current range is introducted. In order to obtain the high accuracy, the proposed technique employs the designed scheme to connect in feedback loop of the basic VCCS based on second generation current conveyor (CCII). This scheme consists of instrumentation and differential amplifiers and one resistor. The performances of the proposed circuit were studied through the use of PSPICE simulation program. Simulation results are agreed with the expected values. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A current signal CMOS sample-and-hold circuit(2007-12-01); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A full-range-360° resolver-to-DC converter(2007-12-01); In this paper, a triangular-to-sawtooth waveform converter and a control logic circuit have been described. Using two designed circuits connected with OTA-based sine-to-triangular wave converter and demodulator, a resolver-to-DC converter is proposed. The converter linearly produces output signal proportional to the shaft angle in full range of 360°. Experimental results verifying the performances of the proposed converter circuit agree well with the theoretical prediction. ©ICROS.