摘要
精度是仪器测量中一个重要的技术指标,该设计采用NE555与被测电容构成多谐振荡器,单片机通过控制多路选择开关选择相应的接入电阻来产生不同的方波信号,实现了档位的自动调节功能,针对大小电容产生信号的差异,分别用测频和测周期的方法有效地减小了误差,然后运用最小二乘算法调节了线性参数,提升了测量电容的精度。
Accuracy is an important technical index in instrument measurement. The design adopts the measured capacitance and NE555 to constitute a multi-vibrator. MCU chooses the corresponding resistance by controlling CD4052multi-channel selector switch to produce different square wave signals so as to realize the automatic selection of gear. In view of the different signal caused by capacitor,the method of frequency measurement and signal period measurement is used to reduce the error effectively,and then the least squares algorithm is used to adjust the linear parameter to improve the accuracy of measuring capacitance.
出处
《仪表技术》
2016年第1期15-18,共4页
Instrumentation Technology
