A high performance CMOS compatible 8-bit current scaling D/A convertor

Author

Singor, H.W. ; Andre, C. ; Salama, C.A.T.

Author_Institution

Dept. of Electr. Eng., Toronto Univ., Ont., Canada

Volume

137

Issue

2

fYear

1990

fDate

4/1/1990 12:00:00 AM

Firstpage

169

Lastpage

174

Abstract

An 8-bit current scaling D/A convertor has been implemented in a standard 3 μm p-well CMOS process. This convertor requires an active area of 1 mm² and is capable of operating at full scale currents ranging from 50 nA to 1 mA. High linearity at low full-scale (FS) currents is achieved by using CMOS compatible lateral bipolar transistors rather than MOS transistors or precision resistors to create the weighted currents. High switching speed is obtained at low current levels through improved current switch design. Test results show that differential nonlinearity is typically ±0.1% FS, integral nonlinearity is ±0.07% FS and the settling time is 35 ns. Two complementary output currents with high output impedance and high voltage compliance are provided

Keywords

CMOS integrated circuits; digital-analogue conversion; 3 micron; 35 ns; 50 nA to 1 mA; 8 bit; CMOS compatible lateral bipolar transistors; DAC; complementary output currents; current scaling D/A convertor; current switch design; high output impedance; high voltage compliance; p-well CMOS process; settling time; weighted currents;

fLanguage

English

Journal_Title

Circuits, Devices and Systems, IEE Proceedings G

Publisher

iet

ISSN

0956-3768

Type

jour

Filename

217049