1、功能说明
    1、OPA PGA模式，放大输入电压2倍
2、使用环境
    软件开发环境：  KEIL MDK-ARM V5.34.0.0
    硬件环境：      基于N32A455VEL7_EVB v1.0.0开发
3、使用说明
    系统配置；
        1、时钟源：
                    HSE=8M,PLL=144M,AHB=144M,APB1=36M,APB2=72M,OPA CLK=36M
        3、端口配置：
                    PA1选择为模拟功能OPA1 VP
                    PA7选择为模拟功能OPA2 VP
                    PC9选择为模拟功能OPA3 VP
                    PC3选择为模拟功能OPA4 VP
                    PA6选择为模拟功能OPA1 OUT
                    PB1选择为模拟功能OPA2 OUT
                    PB11选择为模拟功能OPA3 OUT
                    PB12选择为模拟功能OPA4 OUT
        4、OPA：
                    OPA1 OPA2 OPA3 OPA4 PGA功能，倍数2倍
    使用方法：
        1、编译后打开调试模式，用示波器观察OPA1 OPA2 OPA3 OPA4的输入和输出
        2、OPA输出=2*OPA输入
4、注意事项
    无


1. Function description
    1. OPA PGA mode, amplify the input voltage by 2 times
2. Use environment
    Software development environment: KEIL MDK-ARM V5.34.0.0
    Hardware Environment: Developed based on N32A455VEL7_EVB v1.0.0
3. Instructions for use
    System Configuration;
        1. Clock source:
                    HSE=8M,PLL=144M,AHB=144M,APB1=36M,APB2=72M,OPA CLK=36M
        3. Port configuration:
                    PA1 selected as analog function OPA1 VP
                    PA7 selected as analog function OPA2 VP
                    PC9 selected as analog function OPA3 VP
                    PC3 selected as analog function OPA4 VP
                    PA6 is selected as analog function OPA1 OUT
                    PB1 is selected as analog function OPA2 OUT
                    PB11 is selected as analog function OPA3 OUT
                    PB12 is selected as analog function OPA4 OUT
        4. OPA:
                    OPA1 OPA2 OPA3 OPA4 PGA function, multiples of 2
    Instructions:
        1. Open the debug mode after compiling, and observe the input and output of OPA1 OPA2 OPA3 OPA4 with an oscilloscope
        2. OPA output=2*OPA input
4. Matters needing attention
    none