用于单片集成热真空传感器的Σ-Δ调制器设计  

Design of Σ-Δ Modulator for Monolithic Integrated Thermal Vacuum Sensors

作　　者：李金凤[1,2] 唐祯安[1] 

机构地区：[1]大连理工大学电子工程系,辽宁大连116024 [2]沈阳化工学院信息工程学院,辽宁沈阳110142

出　　处：《微电子学》2010年第4期485-490,共6页Microelectronics

基　　金：国家自然科学基金资助项目(90607003)

摘　　要：设计了一款适用于集成热真空传感器的二阶1位Σ-Δ调制器。该调制器采用前馈通道抑制积分器的输出摆幅、降低谐波失真、提高动态范围。为了降低运算放大器的1/f噪声,积分器中引入相关双采样电路。利用Matlab/Simulink,分析运算放大器的非理想性对调制器性能的影响。调制器由全差分开关电容电路实现。仿真结果表明:在4 MHz采样频率和6.8 kHz信号输入频率-3、dBFS幅值下,电路的最大信噪比为86.9 dB,分辨率可达14位。调制器的有效面积为0.67 mm2。3 V电源电压供电时,功耗为12 mW,各项性能指标均满足设计要求。A 2nd-order single-bit Σ-Δ modulator was designed for integrated thermal vacuum sensor,in which feed-forward paths were adopted to restrain output swing,reduce harmonic distortion and improve dynamic range.Correlated double-sampling circuit was used in the integrator to reduce 1/f noise of the operational amplifier.Effects of non-idealities of the op-amp on the modulator were analyzed with Matlab/Simulink.The modulator was realized by using fully differential switched capacitor circuit.Simulation results showed that the circuit had a peak SNR of 86.9 dB and a 14-bit of resolution at 4 MHz sampling rate and 6.8 kHz input frequency for-3 dBFS amplitude.Consuming 12 mW of power from 3 V supply voltage,the Σ-Δ modulator occupies an active area of 0.67 mm2.And all specifications meet the design target.

关 键 词：集成传感器 Σ-Δ调制器 相关双采样 开关电容电路 

分 类 号：TN761[电子电信—电路与系统]