Calibration algorithm for current-output R-2R ladders

Author

Vargha, Balázs ; Zoltán, István

Author_Institution

Dept. of Meas. & Inf. Syst., Budapest Univ. of Technol. & Econ., Hungary

Volume

50

Issue

5

fYear

2001

fDate

10/1/2001 12:00:00 AM

Firstpage

1216

Lastpage

1220

Abstract

The paper presents a new calibration algorithm for current-output R-2R ladders. The widely used R-2R ladders are easy to realize as an integrated circuit, but the resistance tolerances limit their linearity properties. However, it is possible to achieve higher linearity with self-calibration techniques. A formerly published calibration algorithm by Cutkosky is available for the so-called Cutkosky R-2R ladders. A similar algorithm can be derived for the current-output ladders, which are widely used as multiplying digital-to-analog converters (NMACs) or digital-to-analog converters (DACs). In this paper, the Cutkosky divider is briefly discussed, and then a new description of the inverse ladder is presented as a basis of the calibration algorithm. The calibration algorithm is discussed in detail, and the error budget is analyzed. A simulator was also written to verify the theory

Keywords

calibration; digital-analogue conversion; ladder networks; measurement uncertainty; voltage dividers; Cutkosky divider; Gauss method; binary voltage dividers; binary-weighted voltages; calibration algorithm; current divider stages; current-output R-2R ladders; error budget; internal calibration; inverse ladder; linearity; measurement uncertainty; modified switching concept; multiplying DAC; self-calibration; Algorithm design and analysis; Calibration; Digital-analog conversion; Error analysis; Gaussian processes; Helium; Linearity; Resistors; Switching circuits; Voltage;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/19.963186

Filename

963186