Development of HL80 low ripple high current computer-controlling constant current source

Thermistor has a large temperature range, good stability and resistance to oxidation, which occupies an important position in the low-temperature measurement. This article describes new two-wire thermistor temperature measurement device using the Freescale MC9S12XS128 MCU with sampling capacitance. The device is composed of the MCU with its own A/D, MC9S12XS128 MCU, sampling capacitance, amplifier, boosted circuit, data acquisition and processing system, constant current source, etc. Using constant current source and 16-bit A/D converter designs the temperature measurement circuit, it can eliminate the effect from the conductor resistances in the traditional two-wire resistance temperature measurement system and reduce the measurement error which conductor resistances bring. The method is simple, practical, with high accuracy, strong anti-interference ability and other characteristics.

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Research and Analysis of a Portable Precision Temperature Sensor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.945-949.1924 ◽

2014 ◽

Vol 945-949 ◽

pp. 1924-1931

Author(s):

Hai Qing Yao ◽

Heng Cao ◽

Fei Jiang ◽

Bo Sun

Keyword(s):

Temperature Sensor ◽

Low Cost ◽

Current Source ◽

Control Unit ◽

Constant Current ◽

Interference Signal ◽

Constant Current Source ◽

Differential Signal ◽

Precision Temperature ◽

Micro Control Unit

Based on the excellent performance of Pt100, a portable low-cost precision temperature sensor has been designed, whose core chips are REF03, AD8603, AD7788 and precision resistors. Constant current source (CCS) for 4-wire Pt100 is constituted by REF03, AD8603 and precision resistors. AD7788 measures the differential signal on Pt100 and suppresses the common mode interference signal. Analysis software running on the micro control unit (MCU) filters the digital code from AD7788, and then calculates the current temperature value according to the resistance-temperature mathematical model of Pt100. Analysis and experimental results show that the temperature measurement accuracy of the sensor can reach ±1°C within the range of 0°C-650°C.

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Design of sampling resistor of high power constant-current source

High Power Laser and Particle Beams ◽

10.3788/hplpb20122404.0925 ◽

2012 ◽

Vol 24 (4) ◽

pp. 925-928

Author(s):

赵娟 Zhao Juan ◽

李波 Li Bo ◽

于治国 Yu Zhiguo ◽

曹宁翔 Cao Ningxiang ◽

黄雷 Huang Lei ◽

...

Keyword(s):

High Power ◽

Current Source ◽

Constant Current ◽

Constant Current Source

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Tri Axial Square Helmholtz Coil system at the Alibag Magnetic Observatory: Upgraded to Magnetic Sensor calibration facility

10.5194/gi-2017-47 ◽

2017 ◽

Author(s):

Prasanna Mahavarkar ◽

Jacob John ◽

Vijay Dhapre ◽

Varun Dongre ◽

Sachin Labde

Keyword(s):

Current Source ◽

Helmholtz Coil ◽

Constant Current ◽

Test Facility ◽

Sensor Calibration ◽

Magnetic Observatory ◽

Data Logging ◽

Constant Current Source ◽

Technical Problems ◽

Coil System

Abstract. A Tri Axial Square Helmholtz Coil system for the study of palaeomagnetic studies was successfully commissioned at the Alibag magnetic observatory in the year 1985. This system was used for few years after which the system encountered technical problems with the control unit. Rectification of the same could not be undertaken as the information document related to this system was not available and as a result the said system had been lying in an un-used state for a long time until 2015 when the system was re-commissioned and upgraded as a test facility for calibrating the magnetometer sensors. We have upgraded the system with a constant current source and a data logging unit. Both these units have been designed and developed in the institute laboratory. Also re-measurements of the existing system have been made thoroughly. The upgraded system is semi automatic, enabling non-specialists to operate it after a brief period of instruction. This facility is now in broad use for the parent institute and external institutions to calibrate their magnetometers and also serves as a national facility. Here the design of this system with the calibration results for the space borne fluxgate magnetometers is presented.

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Enhanced Howland-based constant current source for soil ECa measurement

International Journal of Instrumentation Technology ◽

10.1504/ijit.2018.090879 ◽

2018 ◽

Vol 2 (1) ◽

pp. 78

Author(s):

Ritula Thakur ◽

Babankumar S. Bansod

Keyword(s):

Current Source ◽

Constant Current ◽

Constant Current Source

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A Fuzzy Temperature Control System for Pressure-Sensitive Paint Measurement

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.241-244.129 ◽

2012 ◽

Vol 241-244 ◽

pp. 129-134

Author(s):

Jian Guo Mao ◽

Hui Yu Zhang ◽

Guang Min Lu ◽

Jian Kang Xu

Keyword(s):

Control System ◽

Temperature Control ◽

Current Source ◽

Constant Current ◽

Temperature Control System ◽

System Control ◽

Pressure Sensitive Paint ◽

Constant Current Source ◽

Semiconductor Chip ◽

Pressure Sensitive

This template explains a design of a fuzzy temperature control system for the pressure-sensitive paint. According to the relationship between temperature difference and the current of semiconductor chip, the fuzzy system control theory, control the volume of the domain, control rules design, and design a constant current source circuit to control the current through the chip, and finally make experimental verification of the system. The system hardware uses C8051F040 MCU, temperature chip DS18B20, keyboard chip CH451.

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