Common power supply problems and solutions of Arduino

The power supply is roughly USB Power supply ,5V Pin power supply and VIN There are four ways to supply power to pins and power ports .

USB Power supply is to connect the development board to the computer with a data cable ;
5V Pin requires input 5V Stable DC power supply .
VIN Pin requires input 7-12V Direct current , With a voltage stabilizing module, it will be reduced to 5V, You can't go beyond 12V, Easy to overheat .
Power supply voltage of power port 9-12V, It can't be too high .

problem 1： The board is connected to the computer, and the return value of the sensor is normal , It's not normal after using battery power .
solve ： If it is to use VIN Power supply , If lower 7V It may not meet the requirements , The analog voltage input and output of the sensor actually depends on the supply voltage , Then it will cause exceptions .
in addition ,5V and 3V3 Do not connect more than the required voltage .

problem 2： If the motor and the development board need different voltages , How to supply power
solve ： It depends on the power required by the motor and the power that the battery can output , It can be used 7-12V Use the battery directly L298N Such drive motors , Also connect VIN; If the battery power is not enough , You can use two batteries , A set of feed motors , One group is for the development board , But the two and other peripherals must share common ground .