摘要:
A dynamic damper in a lighting driving circuit for limiting an inrush current includes a damper circuit and a timing circuit comprising capacitor. The damper circuit is connected to the timing circuit. When an input voltage is provided to the dynamic damper, the capacitor begins to be charged and the capacitance-voltage of the capacitor rises. The damper circuit enters to a first working state and generates a dynamic damper resistor value. When the capacitance-voltage of the capacitor is greater than a first threshold voltage, the damper circuit enters to a second working state and the dynamic damper resistor value begins to decrease. When the capacitance-voltage of the capacitor is greater than a second threshold voltage, the damper circuit enters to a short-circuit state, and the dynamic damper resistor value decreases to zero to facilitate the normal work of the power source converter.
摘要:
A dynamic damper in a lighting driving circuit for limiting an inrush current includes a damper circuit and a timing circuit comprising capacitor. The damper circuit is connected to the timing circuit. When an input voltage is provided to the dynamic damper, the capacitor begins to be charged and the capacitance-voltage of the capacitor rises. The damper circuit enters to a first working state and generates a dynamic damper resistor value. When the capacitance-voltage of the capacitor is greater than a first threshold voltage, the damper circuit enters to a second working state and the dynamic damper resistor value begins to decrease. When the capacitance-voltage of the capacitor is greater than a second threshold voltage, the damper circuit enters to a short-circuit state, and the dynamic damper resistor value decreases to zero to facilitate the normal work of the power source converter.
摘要:
An auto-selecting holding current circuit is applicable to a converter. A primary side of the converter has a Triode for Alternating Current (TRIAC) and a bleeder circuit. The auto-selecting holding current circuit includes a first sensor module, a second sensor module and a reference voltage selecting circuit. The first sensor module detects an input current drop time or an input voltage drop time to output a sense signal. The second sensor module receives a current detector signal and outputs a critical current signal to detect a holding-current value range of the TRIAC. The reference voltage selecting circuit outputs a reference current signal to the bleeder circuit, and the reference current signal corresponds to a holding-current value of the TRIAC. Therefore, the bleeder circuit maintains normal operation of the TRIACs with different holding-current values.
摘要:
An auto-selecting holding current circuit is applicable to a converter. A primary side of the converter has a Triode for Alternating Current (TRIAC) and a bleeder circuit. The auto-selecting holding current circuit includes a first sensor module, a second sensor module and a reference voltage selecting circuit. The first sensor module detects an input current drop time or an input voltage drop time to output a sense signal. The second sensor module receives a current detector signal and outputs a critical current signal to detect a holding-current value range of the TRIAC. The reference voltage selecting circuit outputs a reference current signal to the bleeder circuit, and the reference current signal corresponds to a holding-current value of the TRIAC. Therefore, the bleeder circuit maintains normal operation of the TRIACs with different holding-current values.
摘要:
A circuit regulator is used to generate a pulse-width-modulation signal, so as to control a power to be selectively input or not input to a primary side of a switching power supply. The circuit regulator includes a synchronous timing pulse generation circuit, outputs a starting pulse after performing signal process of time delay, timing pulse regulation, and synchronization control on a pulse-width-modulation signal and a discharging time signal of a secondary side, and accordingly effectively controls a pulse starting time of the pulse-width-modulation signal. Therefore, the synchronous timing pulse generation circuit can be applied to the circuit regulator, so as to further effectively prevent an inductor current of the switching power supply from entering a Continuous Conduction Mode (CCM).
摘要:
A gas control valve including a body having a throat formed in a bore, a post slidably received in the bore and including a plug, a pin laterally engaged on an upper portion of the post, and a spring for biasing the post so that the plug can be separated from the throat and so that gas may flow through the throat, and a guide fixed in top of the bore and having two inclined surfaces, the ends of the pin are slidable along the inclined surfaces, the plug can engage with the throat when the knob is pushed toward the body so that gas is prevented from flowing through the throat.
摘要:
An Alternating-current-Direct-current (AC-DC dual-use) Light Emitting Diode (LED) driving circuit includes an input power circuit, a buck-boost converter, and a Pulse Width Modulation (PWM) signal controller. The buck-boost converter, including a switching transistor and a feedback resistor, receives a current signal output from the input power circuit, and drives an LED with a driving signal. The PWM signal controller outputs a PWM signal according to the driving signal, so as to sequentially turn on and turn off the switching transistor. One end of the feedback resistor is coupled to the LED, and a floating ground terminal of the PWM signal controller is coupled to the switching transistor and the other end of the feedback resistor. Therefore, the AC-DC dual-use LED driving circuit is capable of dynamically adjusting the duty ratio of the PWM signal without connecting an external photocoupler.
摘要:
An Alternating-current-Direct-current (AC-DC dual-use) Light Emitting Diode (LED) driving circuit includes an input power circuit, a buck-boost converter, and a Pulse Width Modulation (PWM) signal controller. The buck-boost converter, including a switching transistor and a feedback resistor, receives a current signal output from the input power circuit, and drives an LED with a driving signal. The PWM signal controller outputs a PWM signal according to the driving signal, so as to sequentially turn on and turn off the switching transistor. One end of the feedback resistor is coupled to the LED, and a floating ground terminal of the PWM signal controller is coupled to the switching transistor and the other end of the feedback resistor. Therefore, the AC-DC dual-use LED driving circuit is capable of dynamically adjusting the duty ratio of the PWM signal without connecting an external photocoupler.
摘要:
A powering circuit of an AC-DC converter, for converting a high AC input voltage into a low DC output voltage to provide a load voltage in a stable DC bias range, includes a rectifier, a sensing circuit, a control switching circuit, and a voltage regulating capacitor. The rectifier has a primary side coupled to an AC power supply and a secondary side for outputting a DC power supply. The sensing circuit compares the AC input voltage with a preset reference voltage, and turns on a second switch in the control switching circuit when the AC input voltage is lower than the reference voltage, thereby providing a low DC output voltage. The control switching circuit sustains the DC output voltage in a stable DC bias range. Therefore, in addition to reducing the power consumption of the second switch, this circuit structure is simple and can achieve the purpose of circuit integration.
摘要:
This invention discloses a light-emitting semiconductor device with open-bypass function, which comprises two terminals providing a current, at least one LED unit and a bypass switch. Electrodes of the LED unit and the bypass switch are properly connected to the terminals, so that the bypass switch will provide an alternative path for current flowing through if the circuit of the LEDs unit between two terminals is open.