nm131 is a voltage regulator chip, and its parameters are working voltage \/V: 2.8 ~ 5.6; Programming electrical: internal; Maximum supply current \/mA: 10; Maximum current consumption \/μA: 100; CPU: 10B.
The nm131 voltage regulator chip can protect the circuit so that the circuit will not be damaged by the pulse. It also plays a role in adjusting and changing voltage to prevent excessive voltage from burning off the circuit or causing some dangerous damage