DocumentCode :
1478348
Title :
A Precision Current Source Using 
– 
Modulation
Author :
Bergsten, Tobias ; Rydler, Karl-Erik ; Gunnarsson, Ove ; Eklund, Gunnar ; Tarasso, Valter
Author_Institution :
SP Tech. Res. Inst. of Sweden, Boras, Sweden
Volume :
60
Issue :
7
fYear :
2011
fDate :
7/1/2011 12:00:00 AM
Firstpage :
2341
Lastpage :
2346
Abstract :
We present a new source for currents in the picoampere range based on the charging of a capacitor at a constant rate. The voltage ramp is generated using Delta-Sigma modulation and low-pass filtering. This method ensures the linearity of the voltage ramp by calibrating a small number of voltage levels prior to generating the current. Our analysis shows that we can calibrate a picoampere meter with a standard uncertainty of less than 20 μA/A at 10 pA.
Keywords :
capacitors; constant current sources; delta-sigma modulation; low-pass filters; Δ-Σ modulation; capacitor; delta-sigma modulation; low-pass filtering; picoampere range current source; precision current source; standard uncertainty; Calibration; Capacitors; Current measurement; Modulation; Noise; Uncertainty; Voltage measurement; Calibration; capacitance; current measurement; sigma-delta modulation; uncertainty;
fLanguage :
English
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9456
Type :
jour
DOI :
10.1109/TIM.2011.2117250
Filename :
5737787
Link To Document :
