Abstract: A digital multimeter includes a single chip processor, a sound chip connected to the single chip processor, a signal amplifying circuit, a speaker connected to the signal amplifying circuit, and a power source for providing electrical energy for the digital multimeter. The single chip processor collects high and low level signals, and converts the signals into codes which the sound chip can recognize, and transmits the codes to the sound chip. The sound chip converts the codes into audio signals and transmits the audio signals to the signal amplifying circuit. The signal amplifying circuit amplifies the audio signals and outputs the amplified audio signals to the speaker. The amplified audio signals reports the measurement values of the digital multimeter.

Abstract: A digital multimeter includes a single chip processor, a sound chip connected to the single chip processor, a signal amplifying circuit, a speaker connected to the signal amplifying circuit, and a power source for providing electrical energy for the digital multimeter. The single chip processor collects high and low level signals, and converts the signals into codes which the sound chip can recognize, and transmits the codes to the sound chip. The sound chip converts the codes into audio signals and transmits the audio signals to the signal amplifying circuit. The signal amplifying circuit amplifies the audio signals and outputs the amplified audio signals to the speaker. The amplified audio signals reports the measurement values of the digital multimeter.

Abstract: A circuit that can detect computer states. When the computer in a S3 state, a S3 state pin of the computer is at low level, and a S4 state pin of the computer is at high level. A first light emitting diode is turned on and emits light, indicating that the computer is in the S3 state. The circuit also detects an S4 state, a network state, a hard disk state, a network awakening state, a network booting state, a low power state, and a management engine state of the computer according to seven other light emitting diodes.

Abstract: A host computer includes an enclosure, a motherboard mounted in the enclosure. The motherboard includes a battery, a reference voltage generating circuit, an electronic switch, an alarm unit mounted on the enclosure, and a comparator. The reference voltage generating circuit generates a reference voltage. The comparator is connected to the battery and the reference voltage generating circuit to receive the reference voltage and detect a voltage of the battery. The comparator compares the detected voltage of the battery with the reference voltage, and outputs a control signal to turn on the electronic switch to start the alarm unit when the voltage of the battery is less than the reference voltage.

Abstract: A connector includes a holder, a transfer device received in the holder, a sensing device set in the transfer device, and a peripheral interface attached to the holder to be connected to a peripheral device. The sensing device senses whether the peripheral device enters the transfer device. When the peripheral device enters the transfer device, the transfer device drives the peripheral device to move to be plugged into the peripheral interface.

Abstract: A power saving system for a computer incorporating a standby power source includes a setting module, a detecting module and a controlling module. The setting module communicates with the BIOS of the computer and is configured for setting power saving modes on an interface provided by the BIOS for at least one function circuit, during the time the computer powered on. The detecting module is configured for detecting “enable” and/or “disable” signals output from the BIOS. The controlling module includes at least one switching circuit configured for correspondingly interrupting the power supply from the standby power source to one or more of the at least one function circuit after the computer is shut down and the detecting module receives “enable” signals.

Abstract: A connector includes a holder, a transfer device received in the holder, a sensing device set in the transfer device, and a peripheral interface attached to the holder to be connected to a peripheral device. The sensing device senses whether the peripheral device enters the transfer device. When the peripheral device enters the transfer device, the transfer device drives the peripheral device to move to be plugged into the peripheral interface.

Abstract: A circuit for detecting management engine (ME) state of a computer includes first and second electrical switches, and an indicating circuit. The first and second electrical switches are connected to a south bridge of the computer and respectively receive an ME state signal and a startup signal from the south bridge. The ME state signal and startup signal are operable to turn on or turn off the first and second electrical switches to control the indicating circuit to indicate ME state of the computer.

Abstract: A power control circuit includes an input/output controller hub (ICH), and first to third metal-oxide-semiconductor field effect transistors (MOSFETs). A drain of the first MOSFET is connected to a standby power source through a first resistor. A gate of the first MOSFET is connected to a sleep control terminal of the ICH through a second resistor. A drain of the second MOSFET is connected to the drain of the first MOSFET through a third resistor. A gate of the second MOSFET is connected to a general purpose input/output terminal of the ICH through a fourth resistor. A source of the third MOSFET is connected to the standby power source. A gate of the third MOSFET is connected to the drain of the second MOSFET. A drain of the third MOSFET is connected to a power terminal of an onboard network interface card.

Abstract: A host computer includes an enclosure, a motherboard mounted in the enclosure. The motherboard includes a battery, a reference voltage generating circuit, an electronic switch, an alarm unit mounted on the enclosure, and a comparator. The reference voltage generating circuit generates a reference voltage. The comparator is connected to the battery and the reference voltage generating circuit to receive the reference voltage and detect a voltage of the battery. The comparator compares the detected voltage of the battery with the reference voltage, and outputs a control signal to turn on the electronic switch to start the alarm unit when the voltage of the battery is less than the reference voltage.

Abstract: A power control circuit includes an input/output controller hub (ICH), and first to third metal-oxide-semiconductor field effect transistors (MOSFETs). A drain of the first MOSFET is connected to a standby power source through a first resistor. A gate of the first MOSFET is connected to a sleep control terminal of the ICH through a second resistor. A drain of the second MOSFET is connected to the drain of the first MOSFET through a third resistor. A gate of the second MOSFET is connected to a general purpose input/output terminal of the ICH through a fourth resistor. A source of the third MOSFET is connected to the standby power source. A gate of the third MOSFET is connected to the drain of the second MOSFET. A drain of the third MOSFET is connected to a power terminal of an onboard network interface card.

Abstract: A power saving system for a computer incorporating a standby power source includes a setting module, a detecting module and a controlling module. The setting module communicates with the BIOS of the computer and is configured for setting power saving modes on an interface provided by the BIOS for at least one function circuit, during the time the computer powered on. The detecting module is configured for detecting “enable” and/or “disable” signals output from the BIOS. The controlling module includes at least one switching circuit configured for correspondingly interrupting the power supply from the standby power source to one or more of the at least one function circuit after the computer is shut down and the detecting module receives “enable” signals.

Abstract: A circuit that can detect computer states. When the computer in a S3 state, a S3 state pin of the computer is at low level, and a S4 state pin of the computer is at high level. A first light emitting diode is turned on and emits light, indicating that the computer is in the S3 state. The circuit also detects an S4 state, a network state, a hard disk state, a network awakening state, a network booting state, a low power state, and a management engine state of the computer according to seven other light emitting diodes.

Abstract: A circuit for detecting management engine (ME) state of a computer includes first and second electrical switches, and an indicating circuit. The first and second electrical switches are connected to a south bridge of the computer and respectively receive an ME state signal and a startup signal from the south bridge. The ME state signal and startup signal are operable to turn on or turn off the first and second electrical switches to control the indicating circuit to indicate ME state of the computer.

Abstract: An exemplary device for controlling rotation speed of a computer fan includes an identifying device and a control circuit. The identifying device is configured for identifying the type of the computer fan. The control circuit configured for controlling rotation speed of the computer fan includes an electric switch, an integrated circuit, a first output terminal, and a second output terminal. The electric switch has a first terminal coupled to the identifying device to receive an identifying signal, a second terminal coupled to a super I/O chip to receive a PWM signal. The integrated circuit is configured to convert the PWM signal to an analog voltage signal. The first output terminal is configured to output the PWM signal to a PWM control pin of a fan header. The second output terminal is configured to output the analog voltage signal to a power pin of the fan header.

Abstract: An exemplary device for controlling rotation speed of a computer fan includes an identifying device and a control circuit. The identifying device is configured for identifying the type of the computer fan. The control circuit configured for controlling rotation speed of the computer fan includes an electric switch, an integrated circuit, a first output terminal, and a second output terminal. The electric switch has a first terminal coupled to the identifying device to receive an identifying signal, a second terminal coupled to a super I/O chip to receive a PWM signal. The integrated circuit is configured to convert the PWM signal to an analog voltage signal. The first output terminal is configured to output the PWM signal to a PWM control pin of a fan header. The second output terminal is configured to output the analog voltage signal to a power pin of the fan header.