摘要
现有的Delta-Sigmal开关电容调制器模型中,没有考虑积分器的有限直流增益(DCG)非线性因素.通过对非线性DCG分析、估算,给出它的分析、估算与模型.同时给出一套精确的开关电容Δ∑调制器的行为级模型.该模型同时考虑了噪声(开关与运放的热噪声)、时钟抖动,以及非理想情况下,积分器与运放的有限直流增益与单位增益带宽等因素.通过对二阶调制器行为级模型的仿真,验证了非线性有限直流增益会使调制器的输出谐波失真、背景噪声急剧增加,加剧了调制器在行为级上的不可预测性.
The DCG nonlinearity of the integrators, which is not considered in many △∑ modulators' modeling attempts, is analyze, estimated, and modeled by the paper. Precise behavioral modeling of switched-capacitor modulators is presented, considering noise(switches and op-amps thermal noise), clock jitter, nonidealities of integrators and op-arnps including finite dc-gain(DCG) and unity gain band width et. it is shown that neglexting this parameter would lead to a significant undererstimation of the modulators' behavior and increase the noise floor as well as the harmonic distortion at the output of the modulator.
出处
《微电子学与计算机》
CSCD
北大核心
2008年第4期63-67,71,共6页
Microelectronics & Computer