Electronic cigarettes are an electronic product that imitates cigarettes. They have the same appearance, smoke, taste and feel as cigarettes. They are mainly composed of four parts: e-liquid (containing nicotine, flavors, solvent propylene glycol, etc.), heating system, power supply and filter. They produce aerosol with a specific smell for smokers to use through heating and atomization. Among them, MOSFET tubes are usually used in electronic cigarettes for temperature regulation, driving the heating wire to work and protecting the switching function in the circuit.