An electronic device includes a printed circuit board (PCB), a control circuit, and a sensing circuit. The control circuit is configured to determine whether over temperature occurs at one or more detecting points arranged at a first surface of the printed circuit board according to at least one voltage signal. The sensing circuit is arranged at a second surface opposite to the first surface of the printed circuit board and configured to sense the temperature of the one or more detecting points and correspondingly output the voltage signal to the control circuit.