Abstract: A voltage converter is disclosed. The voltage converter includes a constant on time signal generator, a first and second transistors, an inductor, a feedback circuit and a ripple injection circuit. The constant on time signal generator generates a first and second driving signals for driving the first and second transistors. The voltage converter generates an output signal at an output end thereof. The feedback circuit divides the output signal to generate a feedback signal at a feedback end of the voltage converter. The ripple injection circuit gets the voltage of the feedback end and the voltage of the phase end to generate a injection signal. The constant on time signal generator generates the first and second driving signals according to the injection signal, the output signal and a reference signal.

Abstract: A power conversion apparatus is disclosed. The power conversion apparatus includes a power transistor, a thermal resistor and a temperature detection circuit. A control terminal of the power transistor receives a control signal. The power transistor converts an input voltage into an output voltage according to the control signal. The thermal resistor has a negative temperature coefficient. The temperature detection circuit generates the control signal and provides a driving current to the control terminal of the power transistor according to the control signal. The temperature detection circuit further generates an over temperature protection signal according to the driving current.

Abstract: A voltage converting apparatus and a sub-harmonic detector are disclosed. The sub-harmonic detector includes a pulse eliminating circuit, a counter, and a comparator. The pulse eliminating circuit receives a pulse width modulation (PWM) signal and a reference PWM signal having a same period. The PWM signal and reference PWM signal has a plurality of pulses and reference pulses respectively. The pulse eliminating circuit eliminates at least one part of the pulses which overlap with the reference pulses for generating a processed signal. The counter counts the processed signal and the PWM signal during a time period to obtain first and second counting values. The comparator compares the first and second counting values for detecting whether a sub-harmonic condition happens or not in the PWM signal.

Abstract: A voltage converter includes a constant on time signal generator, a first transistor, a second transistor, an inductor, and a ripple injection circuit. The constant on time signal generator generates a first driving signal and a second driving signal. The ripple injection circuit receives an output signal and generates a ripple injection signal. The constant on time signal generator generates the first and second driving signals according to the ripple injection signal, the output signal, and a reference signal.

Abstract: A structure of a fly-back power converting apparatus is disclosed. The structure includes a power transistor, a current detector, a pulse width modulation (PWM) signal generator and a current limiter. The power transistor is coupled to an input voltage and receives a PWM signal. The current detector detects a current output from the power transistor and generates a detecting voltage according to the current. The PWM signal generator generates the PWM signal according to a comparing result by comparing the detecting voltage and a standard voltage. The current limiter generates the standard voltage according to a turn-on time of the power transistor.

Abstract: A buck voltage converting apparatus is disclosed. The buck voltage converting apparatus includes a first transistor, a second transistor, an inductor, a controller and a switch. The first transistor receives an input voltage. A first terminal of the inductor is coupled to the first and second transistors. A second terminal of the inductor is coupled to an output terminal of the buck voltage converting apparatus for generating an output voltage. The controller receives the output voltage, and generates a detection voltage according to voltage amplitude of the output voltage. The switch is coupled between a first terminal of the first transistor and a control terminal of the second transistor. The switch is turned on or off according to the detection voltage.

Abstract: A power supply and its startup circuit are provided. The startup circuit includes a first transistor, a bias resistor, a pull-down switch, a voltage detector, and a discharging path generator. A first end of the first transistor receives alternating current (AC) input power. The bias resistor is serially coupled between a second end and a control end of the first transistor. The pull-down switch is turned on or turned off according to a detection result. The voltage detector generates the detection result by detecting a voltage on the second end of the first transistor. The discharging path generator provides a discharging path between the second end of the first transistor and a reference ground voltage according to the detection result.

Abstract: A voltage converter includes a constant on time signal generator, a first transistor, a second transistor, an inductor, and a ripple injection circuit. The constant on time signal generator generates a first driving signal and a second driving signal. The ripple injection circuit receives an output signal and generates a ripple injection signal. The constant on time signal generator generates the first and second driving signals according to the ripple injection signal, the output signal, and a reference signal.

Abstract: A voltage converter is disclosed. The voltage converter includes a constant on time signal generator, a first and second transistors, an inductor, a feedback circuit and a ripple injection circuit. The constant on time signal generator generates a first and second driving signals for driving the first and second transistors. The voltage converter generates an output signal at an output end thereof. The feedback circuit divides the output signal to generate a feedback signal at a feedback end of the voltage converter. The ripple injection circuit gets the voltage of the feedback end and the voltage of the phase end to generate a injection signal. The constant on time signal generator generates the first and second driving signals according to the injection signal, the output signal and a reference signal.

Abstract: An electric field resistor includes N coils. N coils encircle a common center in sequence, and each of the coils has a first terminal and a second terminal, wherein the first terminal of the first coil receives a first reference voltage, the second terminal of the Nth coil receives a second reference voltage. The second terminal of the ith coil is coupled to the first terminal of the (i+1)th coil, wherein N is a positive integer greater than 1 and 1?i<N. Besides, a distance between the ith coil and the (i+1)th coil is in direct proportion to a voltage difference between the first terminal and the second terminal of the (i+1)th coil.

Abstract: An electric field resistor includes N coils. N coils encircle a common center in sequence, and each of the coils has a first terminal and a second terminal, wherein the first terminal of the first coil receives a first reference voltage, the second terminal of the Nth coil receives a second reference voltage. The second terminal of the ith coil is coupled to the first terminal of the (i+1)th coil, wherein N is a positive integer greater than 1 and 1?i<N. Besides, a distance between the ith coil and the (i+1)th coil is in direct proportion to a voltage difference between the first terminal and the second terminal of the (i+1)th coil.

Abstract: A buck voltage converting apparatus is disclosed. The buck voltage converting apparatus includes a first transistor, a second transistor, an inductor, a controller and a switch. The first transistor receives an input voltage. A first terminal of the inductor is coupled to the first and second transistors. A second terminal of the inductor is coupled to an output terminal of the buck voltage converting apparatus for generating an output voltage. The controller receives the output voltage, and generates a detection voltage according to voltage amplitude of the output voltage. The switch is coupled between a first terminal of the first transistor and a control terminal of the second transistor. The switch is turned on or off according to the detection voltage.

Abstract: A buck power converter includes a power transistor, an inductor, a first diode, and an anti-ringing circuit. The power transistor has a first terminal, a second terminal, and a control terminal. The first terminal of the power transistor receives an input voltage, and the control terminal of the power transistor receives a pulse width modulation (PWM) signal. The anti-ringing circuit detects a detection voltage on the second terminal of the power transistor. According to the detection voltage, the anti-ringing circuit provides at least one second diode serially coupled between the second terminal of the power transistor and a reference ground terminal in a forward-biased manner, so as to clamp a voltage swing of the detection voltage.

Abstract: A power supply and its startup circuit are provided. The startup circuit includes a first transistor, a bias resistor, a pull-down switch, a voltage detector, and a discharging path generator. A first end of the first transistor receives alternating current (AC) input power. The bias resistor is serially coupled between a second end and a control end of the first transistor. The pull-down switch is turned on or turned off according to a detection result. The voltage detector generates the detection result by detecting a voltage on the second end of the first transistor. The discharging path generator provides a discharging path between the second end of the first transistor and a reference ground voltage according to the detection result.

Abstract: A structure of a fly-back power converting apparatus is disclosed. The structure includes a power transistor, a current detector, a pulse width modulation (PWM) signal generator and a current limiter. The power transistor is coupled to an input voltage and receives a PWM signal. The current detector detects a current output from the power transistor and generates a detecting voltage according to the current. The PWM signal generator generates the PWM signal according to a comparing result by comparing the detecting voltage and a standard voltage. The current limiter generates the standard voltage according to a turn-on time of the power transistor.

Abstract: A voltage converting apparatus and a sub-harmonic detector are disclosed. The sub-harmonic detector includes a pulse eliminating circuit, a counter, and a comparator. The pulse eliminating circuit receives a pulse width modulation (PWM) signal and a reference PWM signal having a same period. The PWM signal and reference PWM signal has a plurality of pulses and reference pulses respectively. The pulse eliminating circuit eliminates at least one part of the pulses which overlap with the reference pulses for generating a processed signal. The counter counts the processed signal and the PWM signal during a time period to obtain first and second counting values. The comparator compares the first and second counting values for detecting whether a sub-harmonic condition happens or not in the PWM signal.

Abstract: A power conversion apparatus is disclosed. The power conversion apparatus includes a power transistor, a thermal resistor and a temperature detection circuit. A control terminal of the power transistor receives a control signal. The power transistor converts an input voltage into an output voltage according to the control signal. The thermal resistor has a negative temperature coefficient. The temperature detection circuit generates the control signal and provides a driving current to the control terminal of the power transistor according to the control signal. The temperature detection circuit further generates an over temperature protection signal according to the driving current.

Abstract: A driving device for a LED module is provided. The driving device for the LED module includes a voltage converting unit, a LED module voltage detecting unit, and a switching signal generation unit. The voltage converting unit produces a driving voltage to drive the LED module according to a switching signal. The LED module voltage detecting unit divides the driving voltage to produce a comparison voltage. The switching signal generation unit receives the comparison voltage by a fault detection pin and compares a reference voltage and the comparison voltage to enable or disable the switching signal. After the switching signal is disabled, the switching signal generation unit further pulls up a voltage level of the fault detection pin to a logic high level voltage, so as to produce a fault notification signal to let the fault detection pin also have a function for fault notification.

Abstract: A flyback voltage converter includes a transformer having a primary winding and a secondary winding, a switch serially connected to the primary winding for being switched to produce a current in the secondary winding, and a negative lock loop to adjust the peak value of the current in the secondary winding according to a current conduction time during which the current in the secondary winding is higher than a current threshold, such that the peak value of the current in the secondary winding will be in inverse proportion to the time.

Abstract: A driving device for a LED module is provided. The driving device for the LED module includes a voltage converting unit, a LED module voltage detecting unit, and a switching signal generation unit. The voltage converting unit produces a driving voltage to drive the LED module according to a switching signal. The LED module voltage detecting unit divides the driving voltage to produce a comparison voltage. The switching signal generation unit receives the comparison voltage by a fault detection pin and compares a reference voltage and the comparison voltage to enable or disable the switching signal. After the switching signal is disabled, the switching signal generation unit further pulls up a voltage level of the fault detection pin to a logic high level voltage, so as to produce a fault notification signal to let the fault detection pin also have a function for fault notification.