Opamp gain compensation technique for continuous-time ΣΔ modulators
نویسندگان
چکیده
ELECT A new method that compensates for the low DC gain of nanometre operational amplifiers (opamps) used for high-speed continuous-time (CT) ΣΔ modulators is described. The proposed solution compensates for the integrator’s phase error which is a main limitation produced by the low opamp’s gain. The method uses a simple auxiliary gain stage and a resistor. Simulations of a second-order CT ΣΔ modulator utilising fast single-stage opamps with gain as low as 25 dB verify the effectiveness of the method.
منابع مشابه
An Abstract of the Thesis of Title: Compensation Techniques for Cascaded Delta-sigma A/d Converters and High- Performance Switched-capacitor Circuits All Rights Reserved Compensation Techniques for Cascaded Delta-sigma A/d Converters and High-performance Switched-capacitor Circuits Redacted for Privacy
approved: Gabor C. Temes This thesis describes compensation techniques for cascaded delta-sigma A/D converters (ADCs) and high-performance switched-capacitor (SC) circuits. Various correlated-double-sampling (CDS) techniques are presented to reduce the effects of the nonidealities, such as clock feedthrough, charge injection, opamp input-referred noise and offset, and finite opamp gain, in SC c...
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