Abstract: A computer system includes a display, a motherboard and a power circuit. The display includes a video interface. The motherboard includes a super input-output (SIO) chip. The power circuit includes a first switch unit, a second switch unit, a third switch unit, and an oscillator. When the display is powered on, the video interface outputs a high level signal, the first switch unit is turned on, a power supply powers the oscillator through the first switch unit. The oscillator operates and outputs a high level signal, the second switch unit is turned on, a power-on signal pin of the SIO chip receives a low level signal, and the motherboard is turned on.

Abstract: A method for unlocking a display screen of an electronic device includes activating the display screen which is locked of the electronic device when receiving a communication signal from a key, and generating an unlocked icon on the display screen. A request is sent to the key for generating first audio information after the unlocked icon is pressed, and the first audio information of an unlock code is received from the key. When the first audio information is the same as second audio information generated by a decryption algorithm stored in the storage device of the electronic device, the display screen of the electronic device is unlocked.

Abstract: A protection circuit to prevent power-on operations for a motherboard includes a first power supply, a spring mechanical switch attached to a chassis of an electronic device, a plurality of second power supplies with different voltages, and a plurality of electronic switches. The spring mechanical switch includes a first terminal coupled to the first power supply, and a second terminal grounded. First pins of the electronic switches are coupled to the first terminal, second pins of the electronic switches respectively are coupled to the second power supplies, third pins of the electronic switches are capable of powering the motherboard. When the cover is detached from the chassis, the mechanical switch rebounds, the first terminal disconnects and the second terminal are disconnected, the electronic switches are turned off, no voltages output from the third pins of the electronic switches.

Abstract: A power control device includes a multiple socket-outlet, a power plug and a power supply control circuit. The control circuit includes a power output unit, a first relay and a second relay, a first capacitor, a mechanical switch, an electronic switch and a connector connected to the host of a computer to receive a first voltage. The mechanical switch is turned on to supply power to the multiple socket-outlet, the first relay is closed, the power output unit outputs a working voltage for charging the first capacitor, the electronic switch is turned on, the second relay is closed. If the connector is turned off, the electronic switch is turned off, and the second relay is turned off so that the the multiple socket-outlet is closed.

Abstract: The disclosure provides a motherboard including a north bridge chipset, a basic input output system (BIOS), a first video graphics array (VGA) connector, and a controlling module. The north bridge chipset outputs a sleep signal to the controlling module, the controlling module obtains a switch signal from the first VGA connector, the controlling module outputs a first mode signal to the north bridge chipset according to the sleep signal and the switch signal, the north bridge chipset controls the computer host to be asleep according to the sleep mode. The disclosure also provides a computer control system including the motherboard. The motherboard and the computer control system control the computer to be asleep via a display.

Abstract: A power supply circuit includes first to third electronic switches, first to sixth resistors, and a first capacitor. The power supply circuit is coupled to a USB interface. A control terminal of the first electronic switch is utilized to receive a control signal. A first terminal of the first electronic switch is coupled to a standby power supply. The standby power supply is also coupled to ground through the first capacitor. The second electronic switch is coupled to the first electronic switch. The third electronic switch is coupled between the second electronic and the USB interface. The disclosure further provides an electronic device having the circuit.

Abstract: A power circuit for an electronic device includes an input terminal, an output terminal, a voltage transform unit, and a control unit. The control unit controls the voltage transform unit to operate or not operate, according to the input terminal receives a first voltage or a second voltage. The first voltage is transformed to an output voltage, and is output by the output terminal, when the input terminal receives the first voltage. The second voltage is transmitted from the input terminal to the output terminal through the third switch unit, when the input terminal receives the second voltage. Therefore, the power circuit can receive the first voltage or the second voltage through the input terminal, and outputs the output voltage to other electronic components.

Abstract: A computer system includes a power supply unit (PSU), a matching circuit, and a chip. The matching circuit includes a voltage conversion unit, a voltage-dividing unit, a first resistor, a comparator, a diode, and a delay unit. The comparator includes a non-inverting terminal electrically coupled to the PSU to receive a power-good signal, an inverting terminal electrically coupled to the voltage-dividing unit to receive a reference voltage, and an output terminal. The delay unit is electrically coupled to a power supply and a power-good signal pin of the chip. When a voltage of the power-good signal is greater than the reference voltage, the output terminal of the comparator outputs a high level signal, the diode is turned off and the power supply is delayed by the delay unit and then output to the power-good signal pin of the chip.

Abstract: An alarm circuit includes an audio chip, a basic input and output system (BIOS), a platform controller hub (PCH), and a speaker unit. The audio chip is electrically coupled to the BIOS, the PCH, and the speaker unit. The audio chip receives control signals from the BIOS and the PCH, and controls the speaker unit to alarm according to the control signals.

Abstract: A power supply circuit includes first to third electronic switches, first to sixth resistors, and a first capacitor. The power supply circuit is coupled to a USB interface. A control terminal of the first electronic switch is utilized to receive a control signal. A first terminal of the first electronic switch is coupled to a standby power supply. The standby power supply is also coupled to ground through the first capacitor. The second electronic switch is coupled to the first electronic switch. The third electronic switch is coupled between the second electronic and the USB interface. The disclosure further provides an electronic device having the circuit.

Abstract: The disclosure provides a power supply circuit including a pulse width modulator (PWM), a first voltage conversion unit, a second voltage conversion unit, a conversion chip, and a delay unit. The first voltage conversion unit converts a voltage of a power supply to a first voltage according to pulse signals output by the PWM. The second voltage conversion unit converts the voltage of the power supply to a second voltage according to the pulse signals. The conversion chip converts the first voltage to a third voltage, converts the second voltage to a fourth voltage, and outputs a power-good signal to a south bridge chipset through the delay unit. The disclosure also provides a notebook computer including the power supply circuit.

Abstract: The disclosure provides a power supply circuit including a pulse width modulator (PWM), a first voltage conversion unit, a second voltage conversion unit, a conversion chip, and a delay unit. The first voltage conversion unit converts a voltage of a power supply to a first voltage according to pulse signals output by the PWM. The second voltage conversion unit converts the voltage of the power supply to a second voltage according to the pulse signals. The conversion chip converts the first voltage to a third voltage, converts the second voltage to a fourth voltage, and outputs a power-good signal to a south bridge chipset through the delay unit. The disclosure also provides a notebook computer including the power supply circuit.

Abstract: A computer has a buffering circuit, a power supply circuit, and a controlling circuit. The computer can perform charging operations when the power supply circuit provides power terminals, and perform discharging operations when the power supply circuit powers off unexpected, to provide power to the controlling circuit. The controlling circuit can control the position of a disk head to the track zero of a disk platter of a hard disk drive.

Abstract: A protection circuit to prevent power-on operations for a motherboard includes a first power supply, a spring mechanical switch attached to a chassis of an electronic device, a plurality of second power supplies with different voltages, and a plurality of electronic switches. The spring mechanical switch includes a first terminal coupled to the first power supply, and a second terminal grounded. First pins of the electronic switches are coupled to the first terminal, second pins of the electronic switches respectively are coupled to the second power supplies, third pins of the electronic switches are capable of powering the motherboard. When the cover is detached from the chassis, the mechanical switch rebounds, the first terminal disconnects and the second terminal are disconnected, the electronic switches are turned off, no voltages output from the third pins of the electronic switches.

Abstract: A motherboard includes a first memory, a power supply, a jumper, a second memory slot and a conversion board. A first idle pin of the second memory slot is coupled to the power supply through the jumper. The motherboard supplies power to the first memory and ensures communication with the first memory by virtue of the conversion board. A conversion board is also provided.

Abstract: A power circuit for an electronic device includes an input terminal, an output terminal, a voltage transform unit, and a control unit. The control unit controls the voltage transform unit to operate or not operate, according to the input terminal receives a first voltage or a second voltage. The first voltage is transformed to an output voltage, and is output by the output terminal, when the input terminal receives the first voltage. The second voltage is transmitted from the input terminal to the output terminal through the third switch unit, when the input terminal receives the second voltage. Therefore, the power circuit can receive the first voltage or the second voltage through the input terminal, and outputs the output voltage to other electronic components.

Abstract: The disclosure provides a motherboard including a north bridge chipset, a basic input output system (BIOS), a first video graphics array (VGA) connector, and a controlling module. The north bridge chipset outputs a sleep signal to the controlling module, the controlling module obtains a switch signal from the first VGA connector, the controlling module outputs a first mode signal to the north bridge chipset according to the sleep signal and the switch signal, the north bridge chipset controls the computer host to be asleep according to the sleep mode. The disclosure also provides a computer control system including the motherboard. The motherboard and the computer control system control the computer to be asleep via a display.

Abstract: A computer system includes a power supply unit (PSU), a matching circuit, and a chip. The matching circuit includes a voltage conversion unit, a voltage-dividing unit, a first resistor, a comparator, a diode, and a delay unit. The comparator includes a non-inverting terminal electrically coupled to the PSU to receive a power-good signal, an inverting terminal electrically coupled to the voltage-dividing unit to receive a reference voltage, and an output terminal. The delay unit is electrically coupled to a power supply and a power-good signal pin of the chip. When a voltage of the power-good signal is greater than the reference voltage, the output terminal of the comparator outputs a high level signal, the diode is turned off and the power supply is delayed by the delay unit and then output to the power-good signal pin of the chip.

Abstract: The disclosure provides a voltage test apparatus for CPU serial voltage identification signal including a collecting module, a detecting module, and a processing module. The collecting module obtains the SVID signal from the CPU, the detecting module obtains the work voltage from the CPU. The processing module obtains the SVID signal and the work voltage from the collecting module and the processing module. The processing module converts the SVID signal to an analog voltage. The processing module further compares the work voltage with the analog voltage. The disclosure also provides a testing method for CPU SVID signal.

Abstract: An alarm circuit includes an audio chip, a basic input and output system (BIOS), a platform controller hub (PCH), and a speaker unit. The audio chip is electrically coupled to the BIOS, the PCH, and the speaker unit. The audio chip receives control signals from the BIOS and the PCH, and controls the speaker unit to alarm according to the control signals.