DocumentCode :
88112
Title :
A 10-A High-Precision DC Current Source With Stability Better Than 0.1 ppm/h
Author :
Nong Wang ; Zhengkun Li ; Zhonghua Zhang ; Qing He ; Bing Han ; Yunfeng Lu
Author_Institution :
Sch. of Electr. Eng. & Autom., Harbin Inst. of Technol., Harbin, China
Volume :
64
Issue :
6
fYear :
2015
fDate :
Jun-15
Firstpage :
1324
Lastpage :
1330
Abstract :
The principle, design, and measurement of a 10-A highly stable dc current source is described. Based on a modified low-frequency equivalent model of the MOSFET, we obtain the strict current equation of the MOSFET-based voltage-controlled current source. Factors determining the current stability are investigated and reasonable selection criteria for the key components are discussed. Reasons for oscillation due to the high parasitic capacitance of the paralleled MOSFETs with low set of drain-source voltage are explained and a combined noise gain and lead compensation method is proposed. The best measurement results show that the relative standard deviation and relative drift of the current in 1 h are, respectively, 7.5×10-8 and 2.2×10-8. The current source has been used in our high current meter stability evaluation experiments and can be used for other cases with appropriate improvement, such as the Joule Balance Project to redefine the kilogram at National Institute of Metrology.
Keywords :
MOSFET; circuit oscillations; circuit stability; compensation; constant current sources; electric current measurement; Joule balance project; National Institute of Metrology; current 10 A; current stability; drain-source voltage; high-precision DC current source measurement; highcurrent meter stability evaluation; lead compensation method; modified low-frequency equivalent model; noise gain method; oscillation; paralleled MOSFET; parasitic capacitance; voltagecontrolled current source; Equations; Gain; MOSFET; Mathematical model; Resistors; Stability criteria; Current source; current supply; joule balance; standard current; transconductance amplifier; voltage-controlled current source (VCCS); voltage-controlled current source (VCCS).;
fLanguage :
English
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9456
Type :
jour
DOI :
10.1109/TIM.2014.2376114
Filename :
6982211
Link To Document :
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