An electronic control board including a power supply circuit, a charging circuit, a power failure detection circuit, and a power source switching circuit. AC power is input to the power circuit, and the power circuit converts AC power to DC power to provide the charging circuit. Power supply switching circuit and power failure detection circuit. The AC power supply also has another input in the power failure detection circuit to detect whether the AC power supply has truly lost power. The charging circuit charges the rechargeable battery, which is a power switching circuit. One of them provides power, and the other of the power switching circuit is a power circuit. When the power failure detection circuit does not output a signal to the power switching circuit, the power switching circuit directly outputs the DC power provided by the power circuit to the light source;
When the power failure detection circuit outputs a signal to the power switching circuit, the power switching circuit outputs DC power from the rechargeable battery to the light source; an accommodation space composed of a lamp head connected to the housing and then a lamp cover, which contains an electronic control board, The battery and the light source are connected to each other through a wire;
The led charging light bulb can still illuminate normally for more than three hours after power failure or power failure, giving full play to the function of emergency lighting during power failure