A low-voltage low-power sigma-delta modulator for broadband analog-to-digital conversion

• Published in: IEEE journal of solid-state circuits 2005-09, Vol.40 (9), p.1855-1864
• Main Authors: KiYoung Nam, Sang-Min Lee, Su, D.K., Wooley, B.A.
• Format: Article
• Language: English
• Subjects: Analog circuits; Analog to digital conversion; Analog-digital conversion; Applied sciences; Architecture; Bandwidth; Broadband; Cascades; Circuit properties; CMOS; CMOS analog integrated circuits; CMOS technology; Delta-sigma modulation; Design. Technologies. Operation analysis. Testing; Dielectric, amorphous and glass solid devices; Dynamic range; Dynamic voltage scaling; Electric, optical and optoelectronic circuits; Electronic circuits; Electronics; Exact sciences and technology; Feedforward; Integrated circuit technology; Integrated circuits; low-power electronics; low-voltage analog circuits; mixed analog-digital integrated circuits; Modulators; oversampling A/D converters; Power dissipation; power minimization; Prototypes; Sampling; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; sigma-delta modulation; Signal convertors; switched-capacitor circuits
• ISSN: 0018-9200; 1558-173X
• DOI: 10.1109/JSSC.2005.852161

A cascade of sigma-delta modulator stages that employ a feedforward architecture to reduce the signal ranges required at the integrator inputs and outputs has been used to implement a broadband, high-resolution oversampling CMOS analog-to-digital converter capable of operating from low-supply voltages. An experimental prototype of the proposed architecture has been integrated in a 0.25-/spl mu/m CMOS technology and operates from an analog supply of only 1.2 V. At a sampling rate of 40 MSamples/sec, it achieves a dynamic range of 96 dB for a 1.25-MHz signal bandwidth. The analog power dissipation is 44 mW.