在研究电容式微机械陀螺信号通路工作原理的基础上,分析了影响电容式读出电路精度的各种非理想因素并进行了量化计算,设计了一款低噪声电容读出电路。该芯片采用高频调制原理实现了低频噪声的转移,同时提出了一款具有高电源抑制比的低噪声运算放大器,采用连续时间的电容读出方法研制了微机械陀螺ASIC电路。该芯片采用0.5μm CMOS工艺,芯片面积为3.5mm×3.4 mm,测试结果表明,该单片ASIC的输出级噪底为-117 dB,当陀螺仪量程为±300°/s时,分辨率可以达到0.00035°/s。%Based on the analysis of capacitive vibratory microgyroscope’s interface circuit a low noise capacitive read-out circuit is presented. All kinds of non-ideal factors are discussed. A high power supply rejection ratio of a low-noise amplifier based on continuous time capacitance-to-voltage technique is presented in this paper. Using high frequency modulation principle,the circuit can improve the resolution and dynamic range by canceling 1/f noise. This ASIC is designed and manufactured based on 0.5μm analog CMOS process. The chip size is 3.5 mm×3.4 mm. Measurement shows that the capacitive readout circuit noise floor is-117.14 dB,When the gyro range is ±300 °/s,resolution can be achieved 0.00035 °/s.
展开▼
