Abstract: A battery management system includes a power converter, a first switch, a second switch, a first detecting unit, and a CPU. The power converter is configured to divide current provided by the power supply into a first and a second output current, according to a working current of a system load in a normal state, the first output current is used to power the system load, and the second output current is used to charge a battery unit. The CPU is configured to determine whether the value of current detected by the first detecting unit is greater than a threshold value, and further controls turning on the first switch to power the system load using the first output current, and turn on the second switch to charge the battery unit using the second output current.

Abstract: An under-voltage protection circuit has a power input terminal connected to a battery, a power output terminal connected to an electronic device, a switch circuit for switching the power supply circuit from the power input terminal to the power output terminal, a control circuit for controlling the switch circuit, and a control voltage generating circuit that generates a first control voltage when the switch circuit is cut off. The control circuit controls the switch circuit in accordance with the first control voltage. The control voltage generating circuit further generates a second control voltage when the switch circuit is conductive, and then the control circuit controls the switch circuit in accordance with the second control voltage.

Abstract: An electronic device includes a switching circuit, a hardware (HD) indication unit, a LED module, a software (SF) indication unit, a first control switch electrically connected between a power port, an anode of the LED module, and the HD indication unit, and a second control switch connected between a cathode of the LED module, the SF indication unit and ground. When the electronic device is charged in a powered off state, the cathode of the LED module is grounded, the HD indication unit directs the first control switch to turn on and off alternatingly, and the LED module flashes accordingly. When the electronic device is charged in a powered state, the anode of the LED module is at a high voltage level, and the SF indication unit directs the second control switch to turn on and off alternatingly, and the LED module flashes accordingly.

Abstract: A power switch circuit providing voltage to an output port is provided. The switch circuit includes a single power supply, a switch unit, a controlling unit, and a logic unit. The switch unit is connected between the single power supply and an output port and capable of being turned on and off alternatively for continuing or discontinuing power from the single power supply to the output port; the single power supply provides power to the output port. The controlling unit is configured for generating a voltage controlling signal and transmitting the voltage controlling signal to the logic unit. The logic unit receives and inverts the voltage controlling signal, and outputs the inverted voltage controlling signal to turn on or turn off the switch unit.

Abstract: A forced shutdown circuit includes a manually operable mechanical switch, a first switch circuit including a first switch connected between a power source and a load, a central processing unit (CPU), a second switch circuit including a second switch connected to the first switch, and a delay circuit connected between the mechanical switch and the second switch circuit. When the CPU is in normal, the CPU controls the first switch to be in an “on” or “off” state allowing the power source to power or disconnected from the load according to manual operation on the mechanical switch. When the CPU is in abnormal and the manual operation on the mechanical switch reaches a preset time, the delay circuit is activated to control the second switch to be in an “on” state or in an “off” state to control the first switch to be in the “off” state.

Abstract: An under-voltage protection circuit has a power input terminal connected to a battery, a power output terminal connected to an electronic device, a switch circuit for switching the power supply circuit from the power input terminal to the power output terminal, a control circuit for controlling the switch circuit, and a control voltage generating circuit that generates a first control voltage when the switch circuit is cut off. The control circuit controls the switch circuit in accordance with the first control voltage. The control voltage generating circuit further generates a second control voltage when the switch circuit is conductive, and then the control circuit controls the switch circuit in accordance with the second control voltage.

Abstract: A battery management system includes a power converter, a first switch, a second switch, a first detecting unit, and a CPU. The power converter is configured to divide current provided by the power supply into a first and a second output current, according to a working current of a system load in a normal state, the first output current is used to power the system load, and the second output current is used to charge a battery unit. The CPU is configured to determine whether the value of current detected by the first detecting unit is greater than a threshold value, and further controls turning on the first switch to power the system load using the first output current, and turn on the second switch to charge the battery unit using the second output current.

Abstract: A protection circuit for protecting a rechargeable battery is provided. The protection circuit includes a voltage-threshold generating unit and a comparing unit. The voltage-threshold generating unit is for generating a threshold voltage. The comparing unit is for comparing the threshold voltage to the rechargeable battery voltage and outputting a charging enable signal or a charging disable signal according to the comparison result. The comparing unit outputs the charging enable signal if the amplitude of the threshold voltage is lower than that of the rechargeable battery, or outputs the charging disable signal as the amplitude of the threshold voltage is equal to or higher than that of the rechargeable battery. A battery charger apparatus using the protection circuit is also provided.

Abstract: A power switch circuit providing voltage to an output port is provided. The switch circuit includes a single power supply, a switch unit, a controlling unit, and a logic unit. The switch unit is connected between the single power supply and an output port and capable of being turned on and off alternatively for continuing or discontinuing power from the single power supply to the output port; the single power supply provides power to the output port. The controlling unit is configured for generating a voltage controlling signal and transmitting the voltage controlling signal to the logic unit. The logic unit receives and inverts the voltage controlling signal, and outputs the inverted voltage controlling signal to turn on or turn off the switch unit.

Abstract: An electronic device includes a switching circuit, a hardware (HD) indication unit, a LED module, a software (SF) indication unit, a first control switch electrically connected between a power port, an anode of the LED module, and the HD indication unit, and a second control switch connected between a cathode of the LED module, the SF indication unit and ground. When the electronic device is charged in a powered state, the cathode of the LED module is grounded, the HD indication unit directs the first control switch to turn on and off alternatingly, and the LED module flashes accordingly. When the electronic device is charged in a powered off state, the anode of the LED module is at a high voltage level, and the SF indication unit directs the second control switch to turn on and off alternatingly, and the LED module flashes accordingly.