Comparator-Based Switched-Capacitor Delta-Sigma Modulation
نویسندگان
چکیده
In order to eliminate the use of operational amplifiers (opamps) in sampled-data systems and thus avoid several delicate tradeoffs involved with their design, a new class of switched-capacitor circuits based on comparators was reported. The novelty of this comparator-based switched-capacitor (CBSC) design method is the detection of a virtual ground condition rather than forcing it through feedback as in the case of opamp-based systems. In this paper, the previously reported CBSC circuit was extended to a differential configuration. As an application, firstand second-order low-power lowpass discrete-time ∆Σ modulators with CBSC gain stages were designed and their performance evaluated.
منابع مشابه
A Comparator-Based Switched-Capacitor Delta Sigma Modulator
Comparator-Based Switched-Capacitor (CBSC) is a relatively new topology that replaces opamps in sampled-data systems with a comparator and a set of current mirrors. CBSC is expected to lower power consumption, and to avoid several delicate tradeoffs of op-amp circuits. In this paper, the original single-ended CBSC block is extended to a fully differential version. The differential CBSC is then ...
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