Leadtrend Technology Corporation

Altek Corporation

Ambit Microsystems Corporation

Yi-Shan Chu

Ming-Nan Chuang

Yuan-Wen Chang

Hsing-Kuo Chao

Ren-Yi Chen

Da-Chun Wei

Yu-Bin Wang

Ju-Lin Chia

Yi-Lun Shen

Chun-Teh Chen

Cheng-Chia Hsu

Chin-Ho Wu

Meng-Chi Chiang

Power supplies and power controllers are disclosed. A disclosed power supply has a power controller, a power switch, an auxiliary winding, a first circuit and a second circuit. The power controller is a monolithic integrated circuit with a multi-function pin and a gate pin. A control node of the power switch is coupled to the gate pin. The first circuit is coupled between the multi-function pin and the auxiliary winding and has a diode. The second circuit is coupled between the multi-function pin and a ground line, and has a thermistor.

Power controller with multi-function pin and power supply using the same

An adaptive slope-compensation method is applied for a switch-mode power supply. The switch-mode power supply has a power switch, and an inductor coupled to an input power. The power switch controls the inductor storing energy or releasing energy to generate an output voltage. The adaptive slope-compensation method includes detecting an inductor current passing through the inductor and to generate an inductor-current detecting voltage, detecting a duty cycle of the power switch, detecting a voltage variation of the inductor-current detecting voltage when the power switch is turned on, generating a slope-compensation signal according to the voltage variation and the duty cycle, and adjusting the timing of turning the power switch on or off. In this way, even if the operation conditions of the input power and the output voltage change, the system still can quickly response and does not generate sub-harmonic oscillation.

Adaptive slope-compensation module and method thereof

An apparatus for controlling a charging circuit is provided. The apparatus includes a first detector, a second detector, and a controller. The first detector detects a voltage level at a first time and generates a first indication value corresponding to the voltage level at the first time, where the voltage level corresponds to an output voltage of the charging circuit. The second detector detects the voltage level at a second time after the first time and generates a second indication value corresponding to the voltage level at the second time. The controller receives the first and second indication values, and generates a control signal according to the first and second indication values for turning the charging circuit on and off.

Apparatus for preventing capacitor charger from overcharging and method thereof

A detecting device for detecting an operating mode is disclosed. The detecting device includes a pulse generator and a hold-up unit. The pulse generator is disposed for issuing a one-shot pulse signal in response to each of button signals respectively. The hold-up unit is disposed for receiving the button signals to respectively generate delayed button signals by way of clock delay determined by a clock signal. The one-shot pulse signal and the delayed button signals are used to determine an operating mode of a system.

Detecting device for detecting an operating mode of a system and detecting method thereof

An integrated circuit and a related method for determining an operation mode are disclosed. The exemplified integrated circuit includes a controller, a multi-function pin, and a mode determination circuit. The controller controls a power switch and is being set to operate in one of the operation modes including a first operation mode and a second operation mode. The multi-function pin is connected to an external resistor. The mode determination circuit detects a signal from the multi-function pin. The signal represents the resistance of the external resistor. If the resistance is within a first range, the controller is operated in the first operation mode. If the resistance is within a second range, the controller is operated in the second operation mode.

Integrated circuit and related method for determining operation modes

A control circuit for use in a power converter has a multi-function terminal, a current comparator circuit, and an under-voltage detection circuit. The current comparator circuit compares current flowing through a power switch of the power converter with a reference value through the multi-function terminal when the power switch is on, and turns the power switch off when the current reaches the reference value. The under-voltage detection circuit determines whether an input voltage of the power converter is less than a predetermined value through the multi-function terminal when the power switch is turned off.

Power converter with control circuit and related control method

A pulse width modulation (PWM) control circuit is applied to a power converter with a charging capacitor. The PWM control circuit includes a PWM signal generator, a first comparator, and a reference voltage modulator. A PWM signal generator generates a PWM signal to control a power switch in the power converter. Two input terminals of the first comparator respectively receive a first reference voltage and a sensing voltage, which is proportional to a primary-side current of a transformer. When the power switch is turned on and the sensing voltage rises to the level of the first reference voltage, the first comparator outputs a first control signal to the PWM signal generator. Then, the PWM signal generator outputs a signal to turn off the power switch. The reference voltage modulator outputs the first reference voltage according to a feedback voltage relative to the output voltage of the power converter.

Pulse width modulation control circuit applied to charge output capacitor

A voltage converter includes an electronic induction device, a switch device, a protection circuit, and a control circuit. The switch device, electrically connected to the electronic induction device, is utilized for selectively establishing an electrical connection between the electronic induction device and a predetermined voltage level according to a control signal. The protection circuit, coupled to the electronic induction device, is utilized for selectively establishing an electrical connection between the electronic induction device and the predetermined voltage level, wherein the protection circuit is enabled to establish the electrical connection when a current passing through the switch device exceeds a predetermined current limit. The control circuit, coupled to the switch device, is utilized for generating the control signal.

Voltage converter for preventing switch device from being damaged by voltage spike by utilizing protection circuit

A light emitting diode (LED) driving device includes a power factor correction (PFC) circuit, a bridge switch circuit, a resonant circuit, a transformer and a feedback circuit. The PFC circuit adjusts an output signal thereof based on a feedback signal. The bridge switch circuit transforms the output signal of the PFC circuit into a pulse signal. The resonant circuit resonates and outputs a sinusoidal signal to a primary-side of the transformer based on the pulse signal. The feedback circuit outputs the feedback signal to the PFC circuit in response to a primary-side current of the transformer. Therefore, an output current of the LED driving device is adjusted through modulating the feedback circuit.

Light emitting diode (LED) driving device

A charging device with boundary mode control is disclosed. The charging device includes a transformer, a power switch, a detection circuit and a pulse-width modulation (PWM) controller. The power switch is electrically connected to one end of a primary-side winding of the transformer. The detection circuit is electrically connected to the primary-side winding and the power switch. The detection circuit detects the resonance of the parasitic capacitance of the power switch, thereby generating a detection signal for boundary mode control. The PWM controller generates a pulse-width modulation signal for driving the power switch, and turns on the power switch according to the detection signal.

Charging device with boundary mode control

A high voltage charging circuit is provided with the ability of rapid charging. The circuit is composed of a turn-on control circuit, a turn-off control circuit and a transistor. The turn-on control circuit is adopted to set a turn-on time of a transistor such that the transformer may store magnetic energy, while the turn-off control circuit is used to set a turn-off time of the transistor such that the transformer may release the magnetic energy to charge a high voltage capacitor. Smaller inductance reduces the turn-on time of the power transistor owing to the maximum current of the primary side of the transformer. Therefore, a small-sized transformer may be employed to reduce the volume of the charging circuit with nonoccurrence of saturation.

High voltage charging circuit

The present invention provides an apparatus for controlling a capacitor charging circuit and a method thereof. The apparatus includes a first comparator, a second comparator, and a controller. The first comparator, which is coupled to the charging circuit, receives a voltage level and compares the voltage level with a reference voltage level to generate a first indication signal. The voltage level corresponds to an output voltage of the charging circuit. The second comparator receives a control value and compares the control value with a threshold value to generate a second indication signal. The controller, which is coupled to the charging circuit, the first comparator and the second comparator, generates a control signal according to the first indication signal and the second indication signal to turn the charging circuit on and off, and further generates the control value according to the control signal.

A voltage converter for providing an output voltage signal at an output port according to an input voltage signal is disclosed. The voltage converter comprises a feedback circuit, a transmission switch circuit, a voltage converting circuit, and a pre-bias circuit. The feedback circuit generates a feedback voltage signal according to the output voltage signal. The transmission switch circuit selectively transmits a converted voltage signal to the output port of the voltage converter in a normal mode or transmits the input voltage signal to the output port of the voltage converter in a pre-bias mode. The voltage converting circuit converts the input voltage signal into the converted voltage signal in the normal mode and references the feedback voltage signal and the reference voltage signal to adjust the output voltage signal in the normal mode. The pre-bias circuit controls a magnitude of a current passing through the transmission switch circuit.

Voltage converter capable of avoiding voltage drop occurring in input signal

Disclosed is a capacitor charging module, comprises: a power switch; a power delivery device controlled by the power switch, for providing a charging current to the output capacitor according to a voltage source; a voltage divider for providing a feedback voltage according to the voltage on the output capacitor; a control circuit, for controlling on/off operation of the power switch according to the feedback voltage value, wherein the control circuit turns off the power switch when the voltage level on the output capacitor is at or above the pre-determined value; a first rectifier component, for preventing the feedback voltage being a negative voltage during on periods of the power switch; and a second rectifier component, for preventing an leakage current flowing from the output capacitor to the power delivery device.

Capacitor charging module

A dual loop voltage regulation circuit of power supply chip is provided, comprising a capacitor for providing a voltage signal, a comparator for comparing a first reference voltage signal and the voltage signal to output forward or backward trigger signal, a first switch triggered by a forward trigger signal, a second switch triggered by a backward trigger signal, a first operational amplifier generating a first drive signal while the first and second switches are on, a first transistor switch triggered to be on by a first drive signal to provide a current source loop, a third switch triggered by a forward trigger signal, a fourth switch triggered by a backward trigger signal, a second operational amplifier generating a second drive signal while the third and fourth switches are on, and a second transistor switch triggered to be on by a second drive signal to provide a current sink loop.

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Hsin-Chu, Taiwan

Yi-Shan Chu