Short circuit detection module and short circuit detection method applied thereto

A short circuit detection module applied to an electronic device, the short circuit detection module comprising:

• a power unit including a battery for providing a voltage of the battery;
• a monitoring unit connected with the power unit, the voltage of the battery being inputted into the monitoring unit, and correspondingly a heating current being transmitted to the monitoring unit, the monitoring unit receiving the voltage of the battery;
• a switch unit including a first MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor), the monitoring unit being connected with and coupled with the source electrode of the first MOSFET;
• a heating unit connected with and coupled with the drain electrode of the first MOSFET, the drain electrode of the first MOSFET transmitting the heating current to the heating unit, and the heating unit receiving the corresponding heating current, a heating voltage being generated at an output terminal of the short circuit detection module;
• and
• a control unit connected with and controlling the power unit, the monitoring unit, the switch unit and the heating unit, the control unit being connected with and coupled with the gate electrode of the first MOSFET, the control unit including a PWM (Pulse-Width Modulation) module and a second MOSFET, the drain electrode of the second MOSFET being connected with the gate electrode of the first MOSFET, the control unit adjusting the heating current and the heating voltage to maintain a constant heating voltage by virtue of the PWM module outputting PWM signals to the second MOSFET and the first MOSFET according to different voltages of the battery,
• wherein when the heating current becomes larger, the heating voltage correspondingly becomes larger, and when the heating voltage is greater than a critical value of the heating voltage, the control unit controls the monitoring unit to judge that the short circuit detection module has a short circuit phenomenon, and the control unit turns off the second MOSFET and the first MOSFET.

A short circuit detection method applied to a short circuit detection module of an electronic device, the short circuit detection module including a first MOSFET, and a control unit connected with the first MOSFET, the short circuit detection method comprising steps of:

• reading a voltage of a battery;
• getting a pulse width frequency value of turning on the first MOSFET according to the voltage of the battery, and transmitting the pulse width frequency value to the first MOSFET, and then executing a next step;
• heating the electronic device by a heating voltage of the battery generated at an output terminal of the short circuit detection module;
• reading the heating voltage;
• judging whether the heating voltage is greater than a critical value by the control unit, when the heating voltage is greater than the critical value, a short circuit being shown to be happened, executing a next step to proceed with a short circuit protection, if the short circuit is without being happened, repeating executing the step of reading the voltage of the battery;
• turning off the first MOSFET to proceed with the short circuit protection, after the short circuit protection is proceeded, executing a next step;
• and
• stopping heating the electronic device.