PCB：原理图adc_buffer.SchDoc做小改动


  将AMP_PWR-端口由“输入”改为“接地”

Signed-off-by: fanhx <fanfhx@163.com>
PCB：原理图库中添加电源芯片TPS5430完成

Signed-off-by: fanhx <fanfhx@163.com>
PCB：添加原理图digi_3V3.SchDoc

Signed-off-by: fanhx <fanfhx@163.com>
PCB：完成原理图digi_3V3.SchDoc

   完成了TPS5430-3.3V外围电路的设计，电阻电容大小已标示，序号未标示

Signed-off-by: fanhx <fanfhx@163.com>