常用的运算放大器需要的是正负电源，但是如果你的系统只能提供单一的电源的话，为了能够使你的运放正常工作，推荐看看这个资料-common Operational Amplifiers need is plus or minus power, but if your system can only provide a single power supply, in order to make your Mancin normal work, recommend a look at this information