摘要
介绍了一种带宽可调的二阶低通开关电容滤波器,带宽调节范围为100～500Hz,调节精度约为100Hz。该滤波器用双层金属、双层多晶硅1.2μm的N阱MOS工艺实现,用于一个加速度传感器电路中。设计着重考虑了由时钟信号引起的、严重制约开关电路性能的各种因素,通过优化开关的时序,消除了电荷注入引起的非线性效应,并采用高电源电压抑制比的折叠结构运算放大器,以减轻电源噪声的影响,从而有效地改善了电路的精度。
A second-order low-pass switched-capacitor filter is presented,which has a tunable bandwidth ranging from 100 Hz to 500 Hz with a step of 100 Hz.The filter,which is used in an accelerometer sensor circuit,is fabricated in a 1.2 μm double-metal double-poly N-well CMOS technology. Emphasis is placed on minimizing the signal error induced by the clock signal inherent in switched-capacitor circuits. Dedicated switch timing is proposed to reduce the charge injection,and an operational amplifier with high PSRR is designed to suppress power supply noise.
出处
《微电子学》
CAS
CSCD
北大核心
2003年第6期541-544,549,共5页
Microelectronics
