面向桥式传感器的数字信号调理器

摘要

In order to solve the problems of temperature drift and nonlinearity of the bridge sensors, a digital signal condi-tioner chip was introduced. Firstly, the sensor signal and temperature signal were sampled, amplified and converted into digital domain. Then, the conditioner can provide temperature compensation of sensor offset, sensitivity, and correction of nonlinear sig-nal. Further, the Digital Signal Processing (DSP) unit communicates with microcontroller core through RAM cache. The calibra-tion signal was sent to the microcontroller. The DSP unit was a digital calibration module based on polynomial, and polynomial coefficients were fixed in the ROM of the microcontroller. The digital signal conditioner has the advantages of coefficients of pro-grammable, high flexibility, low cost, high speed, high precision, etc. The results show that the conditioner can effectively im-plement temperature compensation and nonlinear correction of bridge sensors, and it can be widely used in engineering practice.%针对电桥形式的传感器存在温度漂移和非线性的问题,设计了一款信号调理器芯片。首先,调理器对传感器信号和温度信号进行采集、放大,并且转换成数字信号。然后,数字信号处理单元( DSP )对信号进行温度补偿和非线性校准。最后,DSP单元和微控制器核通过RAM缓存通信,将校准后的信号传送到微控制器中。 DSP单元是基于多项式的数字校准模块,多项式的系数固化在微控制器的ROM中。该数字信号调理器具有系数可编程,灵活性高,成本低,速度快,精度高等优点。测试结果表明：该调理器能够有效实现桥式传感器的温度补偿和非线性校正功能,可广泛应用于工程实践中。