Title :
Optimal design of op amps for oversampled converters
Author :
Wang, Feng ; Harjani, Ramesh
Author_Institution :
Dept. of Electr. Eng., Minnesota Univ., Minneapolis, MN, USA
Abstract :
The power consumption for various op amps used in ΣΔ modulators is considered. We first classify the different op amp topologies used in such modulators. We then develop a generalized integrator model that allows us to compare the power consumption for all these topologies. We also derive an expression for the minimum theoretical bound on the power dissipation. We illustrate our results with two design examples: a class A and a class AB op amp. It is shown that class A op amps are the best choice for ΣΔ modulators
Keywords :
circuit optimisation; integrated circuit design; integrating circuits; operational amplifiers; sigma-delta modulation; ΣΔ modulators; A/D convertors; amplifier topologies; class A op amp; class AB op amp; generalized integrator model; oversampled converters; power consumption; Consumer electronics; Data acquisition; Dynamic range; Energy consumption; Feedback; Filters; Power dissipation; Signal to noise ratio; Topology; Voltage;
Conference_Titel :
Custom Integrated Circuits Conference, 1996., Proceedings of the IEEE 1996
Conference_Location :
San Diego, CA
Print_ISBN :
0-7803-3117-6
DOI :
10.1109/CICC.1996.510570
