AD7862及其在智能电子水平仪中的应用

介绍了一种新型的应用于小角度测量的智能电子水平仪的设计。采用差动电容式倾角传感器与温度特性好的精密电阻构成阻容电桥；ICL8038作为交流电桥的激励源；超高速缓冲放大器LH0033和二次线性放大电路组成前置放大器；采用新型的12位A／D变换器AD7862，对电桥不平衡电压经前置放大器放大后的信号及激励源输出电压，作为两路信号同时进行采样和A／D转换，以消除激励源电压波动的影响。最后给出了具体的智能电子水平仪的硬件设计电路。

AD7862 and the Application in Intellectual Electronic Level

Introduce a intellectual electronic level widely used in small angular measurement.In the design,resistance-capacitance bridge is composed by differential capacitance inclination sensor and precise pure resistance with good temperature characteristic;alternating current bridge excitation source is constituted by ICL8038,super-speed buffer amplifier LH0033 and quadratic line amplification circuit compose preamplifier,new style 12-bit ADC AD7862 sample and convert two signal of bridge imbalance voltage simultaneously to eliminate the influence of oscillation of excitation source voltage,one signal is the voltage amplified by pre-amplifier,the other is the output voltage of excitation source.The key points of hardware circuit design of intellectual electronic level are illustrated at the end of the article.