Journal ArticleDOI
An improved frequency compensation technique for CMOS operational amplifiers
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TLDR
In this paper, a two-stage CMOS operational amplifier is proposed to provide stable operation for a much larger range of capacitive loads, as well as much improved V/SUB BB/ power supply rejection over very wide bandwidths for the same basic operational amplifier circuit.Abstract:
The commonly used two-stage CMOS operational amplifier suffers from two basic performance limitations due to the RC compensation network around the second gain stage. First, it provides stable operation for only a limited range of capacitive loads, and second, the power supply rejection shows severe degradation above the open-loop pole frequency. The technique described provides stable operation for a much larger range of capacitive loads, as well as much improved V/SUB BB/ power supply rejection over very wide bandwidths for the same basic operational amplifier circuit. The author presents a mathematical analysis of this new technique in terms of its frequency and noise characteristics followed by its implementation in all n-well CMOS process. Experimental results show 70-dB negative power supply rejection at 100 kHz and an input noise density of 58 nV/(Hz)/SUP 1/2/ at 1 kHz.read more
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References
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Journal ArticleDOI
MOS operational amplifier design-a tutorial overview
Paul R. Gray,Robert G. Meyer +1 more
TL;DR: In this paper, an overview of current design techniques for operational amplifiers implemented in CMOS and NMOS technology at a tutorial level is presented, focusing on CMOS amplifiers because of their more widespread use.
Journal ArticleDOI
A high performance low power CMOS channel filter
TL;DR: In this article, a new CMOS PCM channel filter is described, which includes transmit and receive filters on a single die, and the chip displays an idle-channel noise of typically 0 dBrnC0, a power supply rejection ratio of 40-50 dB at 1 kHz, and a fully operational power dissipation of only 35 mW.
Journal ArticleDOI
High-performance NMOS operational amplifier
TL;DR: A high performance operational amplifier 300 mil/SUP 2/ in area has been designed and fabricated in a standard n-channel silicon-gate enhancement/depletion MOS process.
Journal ArticleDOI
A single-chip CMOS PCM codec with filters
TL;DR: In this paper, a complete PCM codec using charge redistribution and switched-capacitor techniques is described, implemented in a two-level polysilicon CMOS technology using 23.4 mm/SUP 2/ of active area.
Journal ArticleDOI
Low-Power High-Drive CMOS Operational Amplifiers
TL;DR: Low-power CMOS op amps with high-drive capability and good settling characteristics are described, suitable for applications in such systems as charge-redistribution codecs and switched-capacitor filters.