Abstract: An electrical parameter detection device is configured for detecting electrical parameters of a peripheral component interconnect (PCI) connector including a plurality of power pins. The electrical parameter detection device includes a processor module, a first detection module, and a second detection module. The processor module continuously detects voltage values of electric potentials provided by each of the power pins of the PCI connector using the first detection module, and determines time sequences of the electric potentials according to the voltage values of the electric potentials. Furthermore, the processor module detects the amount of power provided by each of the power pins of the PCI connector using the second detection module.

Abstract: A power circuit which is applicable to a data storage device. A boost circuit receives a first voltage and converts it to a second voltage. A charging and discharging circuit receives the second voltage and charges a charging capacitor. As long as a voltage detecting circuit detects that the second voltage exists, it outputs a first selection signal. When the voltage detecting circuit detects that the second voltage does not exist, it outputs a second selection signal and also outputs a signal to the charging and discharging circuit, to release a stored voltage. A voltage selection circuit will output the second voltage according to the first selection signal, or will output the stored voltage from the charging capacitor according to the second selection signal. Buck circuits convert the second voltage or the stored voltage to the different voltages required by a control chip of the data storage device.

Abstract: A printed circuit board (PCB) includes two power supply units, a central processing unit (CPU), two inductors and a temperature compensation resistor. One of the inductor is electrically connected between one power supply unit and the CPU, the other inductor is electrically connected between another power supply unit and the CPU. The temperature compensation resistor is electrically connected between the power supply units and ground, and is positioned between the two inductors to adjust output voltage from the CPU.

Abstract: An overcurrent protection device includes a power input terminal, a power output terminal, a first signal terminal, a second signal terminal, a testing circuit, and a switch element. The power input terminal and the first signal terminal are connected to a power supply. The power output terminal and the second signal terminal are connected to a computer motherboard. If the first and second terminals are disconnected from each other when the computer motherboard works, the power supply stops working. The testing circuit includes a fixed resistor and a control chip parallel connected between the power input and output terminal. The control chip stores a predetermined voltage threshold, and detects voltage between the two terminals of the fixed resistor, and compares the measured voltage with the predetermined voltage threshold. The switch element disconnects the first and second signal terminals when the measured voltage is greater than the predetermined voltage threshold.

Abstract: A sequence control circuit for power sources includes two switched circuits and a sequence control unit. Each of the switched circuits has a control node and is coupled between a power source and a load. The sequence control unit includes two output terminals coupled to the control nodes. The output terminals generate control signals to control the sequence of the circuits being turned on.

Abstract: A motherboard includes a motherboard power supply connector and a time delay circuit. The motherboard power supply connector connects a power supply unit. The motherboard power supply connector has a power supply on pin and a power good pin. The power good pin is configured for receiving a power good signal from the power supply unit. The time delay circuit has an input terminal and an output terminal. The input terminal is configured for receiving a power supply on signal. The output terminal is connected to the power supply on pin and is configured for sending the power supply on signal to the power supply on pin after a time delay determined by the time delay circuit.

Abstract: A detection device to detect a power serving time of a super capacitor for a power-disconnected storage card and an amount of the data packets capable of being stored during the detected serving time is provided. The power-disconnected storage card includes a memory. The detection device includes a power supply unit, the super capacitor, a controller, a storage unit, and a detection unit. The storage unit stores the data packets. The detection unit includes a charge notification module, a data notification module and a time module. The charge notification module generates a first notification signal to the time module. The data notification module generates a second notification signal to the time module when the storage unit transmits the data packet to the memory. The time module records time when the memory completely store the data packet according to the first notification signal and the second notification signal.

Abstract: A buck converter includes a first MOSFET and a second MOSFET connected in series, a PWM module coupled to gates of the first MOSFET and the second MOSFET, and a control unit being coupled to the input current acquired unit, the input voltage acquired unit, the output current acquired unit, the output voltage acquired unit and the PWM module respectively, wherein the control unit controls a switch frequency of the PWM module and acquires the input current, the input voltage, the output current and the output voltage from the input current acquired unit, the input voltage acquired unit, the output current acquired unit and the output voltage acquired unit respectively.

Abstract: A driving voltage adjusting circuit includes a digital rheostat, a control chip, a low dropout regulating circuit, and a driving circuit. The control chip is connected with the digital rheostat, and configured for adjusting the resistance of the digital rheostat. The low dropout regulating circuit is connected with the digital rheostat and outputs an output voltage according to the resistance of the digital rheostat. The driving circuit comprising a number of switch elements connected with each other and a driver configured for driving the switch elements, each of the switch elements comprising a first terminal, a second terminal, and a control terminal configured for controlling connection and disconnection of the first terminal and the second terminal; the first terminal and the second terminal connected with the control chip, the driver is connected with the low dropout regulating circuit and output an driving voltage to the control terminal.

Abstract: A buck converter includes a first electrical switch and a second electrical switch connected in series, a PWM module coupled to the gate of the first electrical switch through a first adjustable resistance module and coupled to the gate of the second electrical switch through a second adjustable resistance module, a filter circuit coupled between the connecting node of the two different electrical switches and an output node, and a control module for adjusting values of the first adjustable resistance module and the second adjustable resistance module and acquiring a voltage value from the connecting node.

Abstract: A power supply circuit for a CPU (central processing unit) includes a CPU, a power supply, a plurality of voltage adjustment modules, a pulse width modulator, a plurality of resistivity selection modules, and a module management unit. The resistivity selection module includes an electronic switch, a first resistor, a second resistor, a third resistor, and a fourth resistor. When the CPU operates abnormally, the power supply circuit utilizes the resistors in the resistivity selection module as voltage dividers, thereby restricting MOSFET or other components to operate in a normal voltage range.

Abstract: A power supply circuit includes a pulse width modulation (PWM) chip, a number of phase circuits, a voltage output end, and a spike suppression circuit. The spike suppression circuit is connected to each of the phase circuits and the voltage output end. The PWM chip controls all of the phase circuits to alternately output power supply voltages according to a predetermined sequence. The spike suppression circuit receives the power supply voltages, and filters out voltage spikes in the power supply voltages, thereby outputting steady voltages to the voltage output end.

Abstract: A driving circuit includes a switching circuit, an acquiring circuit, an amplifying circuit, and an adjusting circuit. The switching circuit includes a driving chip and a switching unit. The switching unit is connected between a power source and a load, the driving chip is configured for controlling the connection and disconnection of the switching unit. The acquiring circuit is connected between the switching unit and the load, and is configured for providing a feedback to the amplifying circuit. The amplifying circuit includes two amplifying input terminals connected to two terminals of the acquiring circuit and an amplifying output terminal outputting an amplified voltage. The adjusting circuit is connected to the amplifying output terminal and is configured for outputting different control voltages to the driving chip according to the amplified voltage. The driving chip outputs different driving voltages to the switching unit according to the control voltages.

Abstract: A resistance determining system and method for a protection circuit, includes a resistance determining unit. The resistance determining unit interconnects a microcontroller and a digital resistor, where the microcontroller has first setting voltage corresponding to a first voltage threshold for activating the protection circuit, and the microcontroller is capable of receiving and converting a first external voltage input to the protection circuit to be a first converted voltage. The digital resistor includes a first variable resistor having two terminals connected to the respective first terminal and the second terminal. The microcontroller adjusts a resistance of the first variable resistor to be a first threshold resistance if the first converted voltage is substantially equal to the first voltage threshold, and the first resistance is determined to be substantially equal to the first threshold resistance.

Abstract: An RC test circuit includes an RC circuit, a digital rheostat, a control chip, and an oscillograph. The RC circuit includes a plurality of positive terminals and a plurality of negative terminals. The digital rheostat includes a plurality of rheostats each including a sliding terminal and a fixed terminal. The sliding terminals are correspondingly connected to the positive terminals while the fixed terminals are correspondingly connected to the negative terminals. The control chip is connected to the digital rheostat, and configured for controlling the digital rheostat to change the resistance of each rheostat. The oscillograph is connected to the RC circuit for displaying a waveform of the RC circuit.

Abstract: A snubber circuit for decreasing a voltage spike of a buck converter includes a resistor unit, a capacitor unit, a detecting unit, and a control unit. The resistor unit provides multiple groups of resistance values. The capacitor unit provides multiple groups of capacitance values. The detecting unit detects voltage spikes of the buck converter corresponding to each group of resistance values and capacitance values. The control unit selects each group of resistance and capacitance to respectively connect to the buck converter and determines a group of resistance and capacitance corresponding to a lowest voltage spike by comparing the detected voltage spikes with each other.

Abstract: A measuring device for a hard disk drive includes a first input node, a hard disk drive having a first input terminal, the first input terminal being coupled to the first input node to provide power to the hard disk drive. A first input current sampling unit is coupled between the first input node and the first input terminal of the hard disk drive to obtain a first input current Iin1. A first input voltage sampling unit is coupled to the first input terminal of the hard disk drive to obtain a first input voltage Uin1. A control unit is coupled to the first input current sampling unit and the first input voltage sampling unit to receive the first input current and the first input voltage.

Abstract: An exemplary motor control circuit for controlling a motor includes a motor driving chip, a sensing unit, and a controller. The motor driving chip motor driving chip is electronically connected to the motor. The sensing unit includes a proximity sensor, the proximity sensor detects whether an external object is proximate to the proximity sensor. The controller is electronically connected to the motor driving chip and the sensing unit, the controller controls the motor driving chip to drive the motor to rotate in a first direction when an external object is detected, and controls the motor driving chip to drive the motor to rotate in a second direction reverse to the first direction when no external object is detected for a predetermined period of time.

Abstract: A motor control circuit for controlling rotation directions of a motor includes a primary power supply, a voltage monitor unit, a motor driving chip, a controller and a backup power supply. The backup power supply is constantly charged by the primary power supply when the primary power supply is in service. The voltage monitor unit is electronically connected to the primary power supply, and is configured for determining whether the primary power supply is in or out of service. The controller controls the motor driving chip to drive the motor to rotate in a first direction when the primary power supply is in service, and alternatively controlling the motor driving chip to drive the motor to rotate in a second direction reverse to the first direction when the primary power supply is out of service.

Abstract: A measurement circuit includes a switch unit with a number of keys selectively pressed to output different resistance regulating signals. A resistance setting circuit receives the resistance regulating signals and connects different resistances to a control circuit. The control circuit obtains a voltage according to the chosen resistance by the resistance setting circuit and compares the voltage with a preset voltage. If the voltage is greater than the preset voltage, the control circuit outputs a high level signal to a control pin of a pulse width modulation (PWM) controller, to control a voltage unit to output a voltage. If the voltage is less than the preset voltage, the control circuit outputs a low level signal to the control pin of the PWM controller, to control the voltage unit to not output a voltage. A display unit displays the chosen resistance.