Petchmaneelumka, Wandee
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Preferred name
Petchmaneelumka, Wandee
Alternative Name
Petchmaneelumka, W.
Main Affiliation
Email
wandee.pe@kmitl.ac.th
9 results
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Item type:Publication, Enhanced sinusoidal amplitude detector for fast response applications(2013-03-28); In this paper, an enhanced sinusoidal-amplitude detector suitable for fast response applications is proposed. Implementation method based on commercially available devices employs a novel control signal generator to improve operation speed of previously reported sinusoidal amplitude detector. The control signal generator used consists of a time-delay circuit, AND logic gate, and three comparators. The enhanced amplitude detector provides faster amplitude detection as well as smaller operation error for amplitude input changes. Experimental results verify a good agreement with theoretical expectation. © 2013 ICIC International. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Resistive-Sensor Interfacing Circuit for Remote Measurement Using CFOA(2024-01-01); ; ; Kaewpoonsuk, AnuchaAn alternative approach to implementing an interfacing circuit for resistive sensor-based remote measurement is presented. The proposed technique uses a Current Feedback Operational Amplifier (CFOA) as an active building block to produce an output voltage linearly related to the resistance of the sensor. Moreover, the accuracy of the output voltage is improved by the enhancement of CFOA. In addition, the proposed circuit provides compensation for the effects of lead-wire resistance. The performance of the proposed technique is discussed in detail and confirmed by PSPICE program simulation and experimental implementation. The resistance decade box is used in the experiment. The maximum error on the output voltage of the experimental results is about 0.4234 %. The experimental results show that the proposed technique provides good performance. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Timer-Based Capacitance-to-Voltage Converter(2026-03-01); This article presents the design and analysis of a capacitance-to-voltage converter based on 555-timer Integrated Circuits (ICs) as the core design element. The circuit structure consists of two primary active components: two 555-timer ICs connected in conjunction with a low-pass filter circuit. The first 555-timer IC operates in astable mode to generate a signal that controls the timing of the second IC. The target capacitor or capacitive sensor to be measured is connected to the second 555-timer IC, which operates in monostable mode. The output signal from the second 555-timer IC is then converted into a DC voltage output using a low-pass filter circuit. The circuit was tested using laboratory capacitors in the range of 52.72 pF to 807.61 pF, and the data were analyzed using Microsoft Excel. The results showed excellent agreement with the measurements obtained from the GW INSTEK LCR-819. The maximum uncalibrated error was found to be −3.32% of full scale. After applying linear curve fitting in Excel, the maximum error was reduced to 0.92% of full scale, confirming the effectiveness of the calibration approach. Furthermore, the circuit was applied to measure the moisture content of paddy rice using a cylindrical capacitive sensor within the moisture range of 12.1% to 23.2%. The experimental data were fitted to a derived equation, which was then used to predict rice moisture content, producing results that corresponded closely with those obtained from the KETT PM-450 grain moisture meter. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Simple resistance-to-period converter for resistive sensors(2012-12-01); ; A method for realization of resistance-to-period converter is introduced in this article. The principle of converter utilizes the behavior of designed astable multivibrator, which is implemented using commercial available and low cost devices. The operation of proposed converter circuit is in current mode. Therefore, the resistance is linearly converted to period and also converted to frequency with invert proportional relationship. The conversion gain of the proposed converter can be adjusted by electronic means. The configuration of the proposed converter is simple and small in size. Experimental results verifying the proposed converter performance are included in detail. The relative error of about 0.8 % is observed. © 2012 ICROS. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A novel resolver-to-DC converter based on OTA-based inverse-sine function circuit(2008-12-01); ; ; A new technique for realizing the resolver-to-DC converter using the OTA-based inverse-sine function circuit is presented. The proposed converter comprises the demodulator, absolute detector, minimum detector, ± unity-gain amplifier, controlled signal logic circuit, and OTA-based inverse-sine function circuit. The output voltage is linearly proportional to the resolver angle with maximum absolute error of about 0.195%, which is less than the error from the conventional resolver-to-DC converter based on the similar OTA-based inverse-sine function circuit. PSPICE simulation and experimental results verifying the performances of the proposed circuit are in close agreement with the expected values. © 2008 SICE. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Pulse induction metal detector using sample and hold method(2011-12-01); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A simple resolver-to-DC converter(2006-12-01); - 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. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Readout circuit for conductivity measurement with parasitic resistance compensation(2018-08-01); ; Kaewpoonsuk, AnuchaThis paper presents a simple method based on commercially available current feedback operational amplifiers (CFOAs) to realize the readout circuit for measuring the solution conductivity including the parasitic resistance in the electrode sensor. The enhanced readout circuit for conductivity measurement in electrolyte solution, compared with the conventional readout circuit using the op-amp inverting amplifier, offers a technique for the parasitic resistance compensation to improve the linearity of the measurement results. The proposed readout circuit provides the digital output which is directly proportional to the conductivity of electrolyte solution. The experimental verification and the measured results of the method are included in this paper.