Abstract: A ground test circuit for a power supply unit includes a sampling circuit, a converting circuit, a processing circuit, and a switch circuit. The sampling circuit detects a voltage difference between a first ground terminal and a second ground terminal. The converting circuit converts the voltage difference to a digital value. The processing circuit compares the digital value to a predetermined value. As long as the digital value is smaller than the predetermined value, the switch circuit allows an external power source to be connected to the power supply unit. Thereby, the ground test circuit controls the connection between the external power source and the power supply unit according to the result of comparison of values done by the processing circuit.

Abstract: A measurement card includes a circuit board, an edge connector on a bottom edge of the circuit board, a port arranged on the circuit board, and a single-pole double-throw switch for connecting the port to either a first or a second pin of the edge connector to tests the VDDQ and VTT outputs of a memory slot.

Abstract: An apparatus tests currents from a plurality of power ports of a power supply unit (PSU), to test minimum value of the currents. The apparatus includes a connector, a controller, a time sequence detection circuit, and a plurality of load circuits. The time sequence detection circuit detects a start time-sequence of the ports of the PSU. Each load circuit is electronically connected to a power port of the PSU. The controller activates and applies each load circuit to a power port of the PSU according the start time-sequence of the ports of the PSU, controls a current-draw of each load circuit until the PSU works in a normal state, and displays the established minimum output current when the PSU works in the normal state.

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 device for testing capacitive loads of a power supply includes a controller, a power supply switching circuit, a capacitive load switching circuit, and a current sampling circuit. The power supply switching circuit selects one of output voltages of the power supply to be electronically connected to the capacitive load switching circuit and the current sampling circuit. The current sampling circuit samples an output current of one output of the power supply selected by the controller. The controller turns on and off switches of the capacitive load switching circuit for matching an output current of the power supply with a reference current until the output current equals to the reference current. The controller outputs a total magnitude of the capacitive loads.

Abstract: A measuring circuit includes a voltage converting circuit, a discharging and sampling circuit, a control circuit, and a charging circuit. The voltage converting circuit converts a voltage to a working voltage and outputs the working voltage to the discharging and sampling circuit. The charging circuit charges a capacitor and outputs a stop charging signal to the control circuit. The control circuit includes a microprocessor with a timer, to output a discharging control signal to the discharging and sampling circuit for controlling the capacitor to discharge according to the stop charging signal. The discharging and sampling circuit includes a discharging resistor, and measures voltages of the capacitor and the discharging resistor. The microprocessor obtains a discharging time of the capacitor for calculating a capacitance of the capacitor, and obtains the voltages of the capacitor and the discharging resistor for calculating a parasitic resistance of the capacitor.

Abstract: A polypeptide comprising a G-CSF domain operably linked to a Tf domain, wherein the ability of the polypeptide to be transported into a cell expressing a TfR gene or the ability of the polypeptide to be transported across a cell expressing a TfR gene via transcytosis is higher than that of the G-CSF domain alone.

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 voltage circuit and a current circuit. The voltage circuit outputs different voltages. The current voltage receives a voltage from the voltage circuit and outputs a current to a capacitor. A detecting circuit measures a temperature of the capacitor and outputs the temperature to the resistance setting circuit. The resistance setting circuit compares the received temperature with a preset temperature. If the received temperature is equal to or greater than the preset temperature, the resistance setting circuit outputs short-circuit information of the capacitor. If the received temperature is less than the preset temperature, the resistance setting circuit outputs normal information of the capacitor. A display unit displays the information of the capacitor.

Abstract: An exemplary electronic load includes a simulation load, a comparison circuit, a sample resistor, and a voltage control circuit. The comparison circuit includes a comparator. The sample resistor samples current flowing through the simulation load, and outputs the sampled current to a negative input of the comparator. An output of the comparator is connected to the simulation load. The voltage control circuit outputs an adjustable control voltage to a positive input of the comparator to control the simulation load to output an adjustable current.

Abstract: A voltage regulating device includes a connector, a slot, a voltage regulating circuit, and a control module. The connector is obtains an initial voltage from an external power supply. The slot is configured for electrically connecting to a load. The voltage regulating circuit is connected between the connector and the slot. In accordance with user input into a keyboard connected to a control microchip as to a voltage level required, the voltage regulating circuit converts the initial voltage to a required test voltage and outputs the required test voltage to the load by the slot. The control microchip controls the voltage regulating circuit to convert the initial voltage into the required test voltage.

Abstract: A solid state disk (SSD) power supply system includes power supply switching circuit. The power supply switching circuit comprises a first power input to receive a first direct current (DC) voltage signal, a second power input connected to a super capacitor to receive a second DC voltage signal provided by the super capacitor, a switching chip connected to the first and second power inputs and configured to select the second DC voltage signals to output in a situation that the first power input is disabled to receive the first DC voltage signal, a voltage converting chip to receive the voltage signal output from the switching chip, and a voltage output to output an operation voltage to an SSD according to the voltage signal. The switching chip and the voltage converting chip respectively output a first and second test signals for testing a discharging time of the super capacitor.

Abstract: An apparatus is configured for calibrating a test value of an output current of a digital power supply. The power supply has a control chip configured for detecting and outputting the test value of the output current. The apparatus includes a keyboard circuit, a digital potentiometer and a controller. The keyboard circuit is configured for inputting an actual value of the output current. The digital potentiometer is electronically connected to the control chip. The controller receives a test value and the actual value of the output current respectively from the control chip and the keyboard, determines whether the test value is equivalent to the actual value, adjusts the test value of the output current by adjusting an effective resistance of the digital potentiometer until the test value equals the actual value, and outputs the effective resistance of the digital potentiometer when the test value equals the actual value.

Abstract: A power switch circuit includes a control circuit, and first and second detecting circuits. The control circuit includes first and second field effect transistors (FETs) and first and second sensing resistors. The first detecting circuit includes two input terminals connected to the first and second ends of the first sensing resistor and an output terminal connected to the first FET. The first detecting circuit controls the first FET to be turned on or turned off according to the voltages of the first and second ends of the first sensing resistor. The second detecting circuit includes two input terminals connected to the first and second ends of the second sensing resistor and an output terminal connected to the second FET. The second detecting circuit controls the second FET to be turned on or turned off according to the voltages of the first and second ends of the second sensing resistor.

Abstract: A measurement card includes a circuit board, an edge connector on a bottom edge of the circuit board, a port arranged on the circuit board, and a single-pole double-throw switch for connecting the port to either a first or a second pin of the edge connector to tests the VDDQ and VTT outputs of a memory slot.

Abstract: A balancing resistor testing apparatus is configured for acquiring a resistance of a balancing resistor electronically connected to a supercapacitor of a series supercapacitor assembly in parallel. The balancing resistor testing apparatus includes a controller and a digital potentiometer. The controller detects a voltage across each supercapacitor of the series supercapacitor. The digital potentiometer comprising a plurality of variable resistors each of which is electronically connected to a supercapacitor in parallel, the controller controls the digital potentiometer to continuously adjust the effective resistance of each potentiometer until the controller detects that each supercapacitor has the same or very similar voltage.

Abstract: A circuit for measuring the DC resistance of an inductor includes an input unit, a microprocessor module, a current source and a voltage detecting unit. The microprocessor module receives signals from the input unit and generates different signals to command constant currents through the inductor by the current source. The voltage detecting unit reads voltages of the inductor and outputs the voltages obtained to the microprocessor module. According to the currents and the voltages read, the microprocessor module may calculate the DC resistance(s) of the inductor.

Abstract: An input power measuring device includes a board with an edge connector, a first dual inline memory modules (DIMM) socket, a resistor, a differential amplifier circuit, a voltage dividing circuit, a display screen, and a controller. When the edge connector is inserted into a second DIMM socket of a motherboard and the motherboard is powered on, the resistor samples first current, and converts the first current into a first voltage. The differential amplifier circuit amplifiers the first current to a second current. The voltage dividing circuit divides the first voltage, and outputs a second voltage. The controller converts the second current into a third current, converts the second voltage into a third voltage, and calculates a power according to the third current and the third voltage.

Abstract: A driver circuit drives a pulse width modulation (PWM) controller. The driver circuit includes an enabling circuit, a power supply input control circuit, a stabilizing circuit, and a discharge circuit. The stabilizing circuit is electrically connected to the PWM controller. The power supply input control circuit is electrically connected between the enabling circuit and the stabilizing circuit. The discharge circuit is electrically connected between the stabilizing circuit and the ground. In response to the driver circuit working in normal operation, the enabling circuit enables the power supply input control circuit to output a working voltage to the stabilizing circuit, and in response to the process of the driver circuit restarting, the enabling circuit enables the power supply input to stop outputting power supply to the stabilizing circuit. The discharge circuit leads a residual voltage of the stabilizing circuit to the ground, during the process of the driver circuit being restarted.

Abstract: An adjusting device adjusts a load line of a CPU power supply circuit. The adjusting device includes a controller, a DC electronic load device, a voltage follower, an adjustable resistor, and an indicator. The controller controls the DC electronic load device to change an output current of the circuit. The voltage follower sends an output voltage of the circuit to the controller. The controller calculates the load line of the circuit based on the output current and the output voltage of the circuit, determines whether the load line satisfies the required value, changes a resistance of the adjustable resistor until the load line satisfies the required value, and sends a resistance of the adjustable resistor to the indicator.

Abstract: A resistance determining system is used to determine an offsetting resistance of a mainboard to establish a predetermined offset voltage. The system includes an input equipment, a single-chip, and a resistor. The input equipment sets a predetermined standard voltage of the mainboard. The resistor supplies the mainboard with various resistances, to adjust real output voltage of the mainboard. The single-chip monitors the real output voltage of the mainboard, and adjusts the resistance of the resistor until the difference between the real output voltage and the predetermined standard voltage is equal to a predetermined offset voltage.