A 0.5μm CMOS programmable discrete-time Δ-Σ modulator with floating gate elements

Author

Pereira, Angelo W. ; Allen, Daniel J. ; Hasler, Paul E.

Author_Institution

Sch. of Electr. & Comput. Eng., Georgia Inst. of Technol., Atlanta, GA, USA

Volume

1

fYear

2004

fDate

23-26 May 2004

Abstract

This paper describes a tunable Δ-Σ modulator using floating gate elements. In a previous work, the feasibility of using these structures in a conventional switch capacitor modulator was shown. Floating gate electronic potentiometers (e-pots) in the modulator loop were used to provide convenient and accurate programmable on-chip reference voltages. These voltages determined the feedback coefficients of the modulator. In this work time-domain modelling of the modulator in SIMULINK as well as SPICE simulations is used to predict optimal coefficients, which are programmed into the modulator at runtime. Simulation and experimental results for a 2nd order modulator are presented. The modulator achieves 57 dB peak SNR and 55 dB SINAD giving ENOB=9 bits.

Keywords

CMOS integrated circuits; SPICE; circuit feedback; circuit tuning; discrete time systems; potentiometers; programmable circuits; reference circuits; sigma-delta modulation; switched capacitor networks; time-domain analysis; 0.5 micron; 2nd order modulator; 57 dB; CMOS; SIMULINK; SPICE simulations; discrete-time Δ-Σ modulator; electronic potentiometers; feedback coefficients; floating gate elements; modulator loop; optimal coefficients; programmable ΔΣ modulator; programmable on-chip reference voltages; switch capacitor modulator; time-domain modelling; tunable Δ-Σ modulator; Capacitors; Delta modulation; Feedback; Modulation coding; Potentiometers; Predictive models; SPICE; Switches; Time domain analysis; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems, 2004. ISCAS '04. Proceedings of the 2004 International Symposium on

Print_ISBN

0-7803-8251-X

Type

conf

DOI

10.1109/ISCAS.2004.1328169

Filename

1328169