Abstract: A temperature control system includes a temperature control circuit having a plurality of predetermined temperature values, a switch control circuit and a heating control circuit. The temperature control circuit outputs control signals according to the plurality of predetermined temperature values. The switch control circuit turns on according to the control signals and outputs the DC voltage to the heating control circuit which begins to get hot. The temperature control circuit detects a temperature of the heating control circuit from time to time and turns off the switch control circuit when the temperature of the heating control circuit is equal to a selected predetermined temperature.

Abstract: A Light Emitting Diode (LED) driving circuit includes a power supply circuit, an LED circuit, and a switch control circuit. The power supply circuit includes an energy storage device and a switch component connected to the energy storage device. The energy storage device stores electric power when the switch component is switched on. The LED circuit is connected to the energy storage device. The switch control circuit is connected to the switch component, and is adapted to control the on/off states of the switch component, thereby adjusting a current flowing through the LED circuit.

Abstract: A system for testing a computer includes a single chip microcontroller (SCM), an environmental test chamber, and a control device connected to the SCM and the environmental test chamber. The SCM repeatedly switches the computer on and off and monitors the computer's response. The environmental test chamber accommodates the computer. The control device receives monitored data from the SCM and controls temperature and humidity in the environmental test chamber.

Abstract: A system for testing a motherboard performance includes a control device, a voltage processing circuit, a voltage regulating circuit and a voltage feedback circuit. The control device stores a plurality of predetermined voltage values and outputs control signals according to the plurality of predetermined voltage values. The voltage processing circuit receives the control signal and outputs a plurality of PWM signals according to the control signal. The voltage regulating circuit receives the plurality of PWM signal and outputs a plurality of DC voltage to a plurality of voltage input terminals of the motherboard. The voltage feedback circuit collects voltage signals at the plurality of voltage input terminals of the motherboard.

Abstract: An alarm system for emitting an alarm includes a distance detecting circuit, a gate circuit, a voltage conversion circuit, a distance judging circuit and an alarm circuit. The distance detecting circuit receives a first signal, detects a distance between an object and the alarm system, outputs a second signal and a third signal according to the distance. The gate circuit receives the second signal and the third signal and outputs a voltage level signal. The voltage conversion circuit receives the voltage level signal and converts the voltage level signal into a DC voltage signal. The distance judging circuit receives the DC voltage signal and compares the DC voltage signal against a reference voltage signal to output a control signal if necessary. The alarm circuit receives the control signal and produces the alarm when the distance between the object and the alarm system is less than a threshold distance.

Abstract: A computer turning on/off testing apparatus for turning on a computer automatically includes a control module, a switch module, and a power supply module. The control module outputs control signals and receives a turn on signal from the computer to determine whether the computer turns on successfully. The switch module receives the control signals and turns on/off the computer according to the control signals. The power supply module provides power to the control module and the switch module. The control module stores a predetermined test time. The control module records abnormal information and test times when the computer turns on/off, and outputs the control signals to turn on the computer again when the computer cannot restart. The computer is turned on and off until a turning on/off time of the computer is equal to the predetermined test time.

Abstract: A power supply circuit includes a voltage regulating circuit, a control circuit, and a switch circuit. The voltage regulating circuit receives an AC voltage signal from a live wire output terminal and converts the AC voltage signal to a control signal. The control circuit receives the control signal and turns on or turns off an electronic connection from the AC voltage signal to the switch circuit according to the control signal. The switch circuit is configured to be powered on and output the AC voltage signal when the electronic connection from the AC voltage signal to the switch circuit is turned on.

Abstract: A test apparatus for a thermal resistor includes a control device, a temperature processing circuit, a voltage regulating circuit and a temperature detecting circuit. The control device stores a plurality of predetermined voltage values and outputs control signals according to those predetermined values. The temperature processing circuit receives the control signals and outputs a pulse width modulation (PWM) signal according to the control signal. The voltage regulating circuit receives the PWM signal and outputs a first direct current (DC) voltage to heat the thermal resistor. The temperature detecting circuit detects temperature signals and current signals from the thermal resistor. The control device receives the temperature signals and current signals of the thermal resistor and generates a resistance-temperature graph of the thermal resistor.

Abstract: A detecting circuit includes an indicating light, a switch component, and a control component. The indicating light indicates whether a voltage rail output by a power supply is within a predetermined voltage range. The switch component has a first terminal connected to the voltage rail, a second terminal connected to the indicating light, and a control terminal. The control component is connected to the control terminal of the switch component. The control component switches on the switch component to power on the indicating light when the voltage rail is within the predetermined voltage range, or switches off the switch component to power off the indicating light when the voltage rail is out of the predetermined voltage range.

Abstract: A circuit includes a power supply circuit and a measuring circuit. The measuring circuit includes a voltage meter, a current meter, and a connector connected to a zener diode under test. The voltage meter is connected to the connector in parallel. The current meter is configured to measure a current flowing through the zener diode. The power supply circuit is capable of providing an output voltage that becomes greater gradually. The voltage meter is capable of obtaining a breakdown voltage of the zener diode when the current flowing through the zener diode increases and a voltage across the zener diode is unchanged.

Abstract: A computer startup test apparatus for turning on a computer automatically, includes a control module, a switch module, and a startup module. The control module is configured to output control signals, data signals and clock signals. The switch module is configured to receive the control signals, and turn on the computer according to the received control signals. The startup module is configured to receive the data signals and clock signals, and restarts the computer according to the received data signals and clock signals. The control module stores a predetermined test time. The control module records abnormal information and test times when the computer restarts, and outputs the control signals to turn on the computer using the switch module when the computer cannot restart.

Abstract: A Universal Series Bus USB port detection and testing circuit, configured to detect the voltage output of a USB port of an electronic device, includes a voltage comparing circuit and an indicating circuit. The indicating circuit is connected to an output terminal of the voltage comparing circuit. The voltage comparing circuit compares the voltage output from the USB port against a reference voltage and output a signal whereby the indicating circuit indicates whether the voltage is within, or above, or below, the standard range.

Abstract: A Light Emitting Diode (LED) driving circuit includes a power supply circuit, an LED circuit, and a switch control circuit. The power supply circuit includes an energy storage device and a switch component connected to the energy storage device. The energy storage device stores electric power when the switch component is switched on. The LED circuit is connected to the energy storage device. The switch control circuit is connected to the switch component, and is adapted to control the on/off states of the switch component, thereby adjusting a current flowing through the LED circuit.

Abstract: A system for testing a computer includes a single chip microcontroller (SCM), an environmental test chamber, and a control device connected to the SCM and the environmental test chamber. The SCM repeatedly switches the computer on and off and monitors the computer's response. The environmental test chamber accommodates the computer. The control device receives monitored data from the SCM and controls temperature and humidity in the environmental test chamber.

Abstract: A system for testing a motherboard performance includes a control device, a voltage processing circuit, a voltage regulating circuit and a voltage feedback circuit. The control device stores a plurality of predetermined voltage values and outputs control signals according to the plurality of predetermined voltage values. The voltage processing circuit receives the control signal and outputs a plurality of PWM signals according to the control signal. The voltage regulating circuit receives the plurality of PWM signal and outputs a plurality of DC voltage to a plurality of voltage input terminals of the motherboard. The voltage feedback circuit collects voltage signals at the plurality of voltage input terminals of the motherboard.

Abstract: A test apparatus for a thermal resistor includes a control device, a temperature processing circuit, a voltage regulating circuit and a temperature detecting circuit. The control device stores a plurality of predetermined voltage values and outputs control signals according to those predetermined values. The temperature processing circuit receives the control signals and outputs a pulse width modulation (PWM) signal according to the control signal. The voltage regulating circuit receives the PWM signal and outputs a first direct current (DC) voltage to heat the thermal resistor. The temperature detecting circuit detects temperature signals and current signals from the thermal resistor. The control device receives the temperature signals and current signals of the thermal resistor and generates a resistance-temperature graph of the thermal resistor.

Abstract: A temperature control system includes a temperature control circuit having a plurality of predetermined temperature values, a switch control circuit and a heating control circuit. The temperature control circuit outputs control signals according to the plurality of predetermined temperature values. The switch control circuit turns on according to the control signals and outputs the DC voltage to the heating control circuit which begins to get hot. The temperature control circuit detects a temperature of the heating control circuit from time to time and turns off the switch control circuit when the temperature of the heating control circuit is equal to a selected predetermined temperature.

Abstract: An alarm system for emitting an alarm includes a distance detecting circuit, a gate circuit, a voltage conversion circuit, a distance judging circuit and an alarm circuit. The distance detecting circuit receives a first signal, detects a distance between an object and the alarm system, outputs a second signal and a third signal according to the distance. The gate circuit receives the second signal and the third signal and outputs a voltage level signal. The voltage conversion circuit receives the voltage level signal and converts the voltage level signal into a DC voltage signal. The distance judging circuit receives the DC voltage signal and compares the DC voltage signal against a reference voltage signal to output a control signal if necessary. The alarm circuit receives the control signal and produces the alarm when the distance between the object and the alarm system is less than a threshold distance.

Abstract: A Universal Series Bus USB port detection and testing circuit, configured to detect the voltage output of a USB port of an electronic device, includes a voltage comparing circuit and an indicating circuit. The indicating circuit is connected to an output terminal of the voltage comparing circuit. The voltage comparing circuit compares the voltage output from the USB port against a reference voltage and output a signal whereby the indicating circuit indicates whether the voltage is within, or above, or below, the standard range.

Abstract: A charging circuit includes a DC (Direct Current) power source, a rechargeable battery, and a switch circuit. The DC power source includes positive and negative output terminals, and the switch circuit is connected to and located between the DC power source and the rechargeable battery. The switch circuit comprises an arrangement of transistors and other components which permits the connection of the battery in any manner, and the normal charging or recharging of the battery notwithstanding the polarity of the battery terminals.