Leadtrend Technology Corporation

Ming-Chang Tsou

Meng-Jen Tsai

Chih-Chi Chang

Hsien-Te Huang

Chung-Wei Lin

Kuo-Chien Huang

Jun-Hao Huang

Jiun-Sheng Huang

Ren-Yi Chen

Hung-Ching Lee

Da-Chun Wei

Kuan-Hsien Chou

Yao-Tsung Chen

Mao-Shih Li

Tsung-Chien Wu

Yi-Chuan Tsai

Pai-Feng Liu

Ruei-Jhih Jheng

Chin-Ho Wu

Shun-Chin Chou

Hung-Ting Hsu

Chao-Chih Lin

Tzu Chen Lin

Fong-Cheng Yang

Yao-Wei Hsieh

Da-Jin Chen

Hung Kuang Liu

Ming-Yen Lin

Shih Yi Yang

Chih-Pu Yeh

Chih-Nan Hsia

Ru-Hung Lu

Shun-Yao Liu

Cheng-Tsung Ho

Yu-Kun Lin

Ya-Fu Huang

A primary-controller with voltage compensation function applied to a primary side of a power converter includes a gate control signal generation circuit, and the gate control signal generation circuit includes a clamping unit and a driving unit. The gate control signal generation circuit is coupled to a power switch installed in the primary side of the power converter, and is used for enabling a gate control signal, wherein the gate control signal is used for making the power switch turned on. The clamping unit generates a compensation voltage according to a clamping voltage. The driving unit is coupled between the clamping unit and a gate of the power switch, and used for generating the gate control signal according to the compensation voltage. The clamping voltage is changed with a detection voltage of a detection resistor coupled to the power switch accordingly.

Primary-controller with voltage compensation function and operational method thereof

A power supply has multiple DC power sources converted from an AC power source. The power supply has an isolated converter converting the AC power source into an intermediate DC power source, and non-isolated converters converting the intermediate DC power source into the DC power sources, regulated at target output values respectively. A communication channel connects the isolated converter and one of the non-isolated converters, and transmits a feedback signal in association with the target output values. The isolated converter, in response to the feedback signal, regulates the intermediate DC power source at an intermediate target value related to the target output values.

Power supplies with multiple output ports, and control methods thereof

A control method is in use of an interleaved power converter with first and second power stages for generating an output power source. A compensation is generated in response to a feedback signal and a reference voltage, and the feedback signal represents the output power source. The output power of the first power stage is controlled to supply to the output power source in response to the compensation signal. The operation status of the second power stage is switched in response to the compensation signal and the feedback signal, and is prevented from being switched when the feedback signal is beyond a stable range covering the reference voltage.

Control methods for interleaved power converter

A controller applied to a power converter is installed in a primary side of the power converter. The controller includes a capacitor, an adjustment signal generation circuit, and a discharge circuit. The capacitor is used for generating a tracking voltage. The adjustment signal generation circuit is used for generating an adjustment signal according to a feedback voltage and the tracking voltage. The discharge circuit is used for discharging the capacitor according to the feedback voltage and the adjustment signal. The tracking voltage is used for tracking a state of a magnetizing current of a magnetizing inductor of the primary side of the power converter, and when the tracking voltage consists with the state of the magnetizing current, the tracking voltage is applied to at least one of zero-voltage switching (ZVS) control and quasi-resonant (QR) control of the power converter.

Controller applied to a power converter and operational method thereof

A control method in use of a flyback power converter is disclosed to provide an operation power source supplying power to a power controller controlling a main power switch. The flyback power converter has a transformer with a primary winding and an auxiliary winding. The main power switch and the primary winding are connected in series. A chopper switch and a buffer inductor are connected in series between the auxiliary winding and the power controller. The power controller turns ON the main power switch for an ON time to energize the transformer, and turns ON the chopper switch for at least a time period during the ON time, so that during the time period the buffer inductor conducts an induced current flowing from the auxiliary winding and through the chopper switch, to build up the operation power source.

Flyback power converters and control methods thereof

A connector controller controls a connector with a power pin, a communication pin, and a ground pin. The connector detects the voltage at the communication pin at least twice to generate first and second voltages respectively. A bus power is supplied at the power pin. The first voltage is detected when a bus current to/from the bus power is about zero. The connector controller controls the bus power in response to a difference between the first and second voltage.

Power management control method in use of connector

The invention discloses a control method in use of a synchronous rectifier controller, controlling a synchronous rectifier in a power supply supplying power a load. The synchronous rectifier is turned ON in response to a terminal signal of the synchronous rectifier. An ON-time of the synchronous rectifier is made not less than a minimum ON-time. A detection result in association with the load is provided, for determining the minimum ON-time. The minimum ON-time is a first period when the detection result indicates the load as a first load, and a second period, shorter than the first period, when the detection result indicates the load as a second load heavier than the first load.

Control methods for changing minimum on-time of synchronous rectifier and related synchronous rectifier controllers

A control method of a flyback power converter includes a voltage detection pin detecting conduction time of a power switch of a primary side of the flyback power converter, a feedback pin detecting conduction time of a synchronous switch of a secondary side of the flyback power converter, the feedback pin detecting a number of inductor capacitor resonant valleys when the flyback power converter operates in a discontinuous conduction mode, and a high voltage detection pin detecting an input voltage inputted in the flyback power converter; and a controller applied to the flyback power converter making the flyback power converter operate in a quasi-resonant mode when the number of the inductor capacitor resonant valleys is greater than a predetermined number, an operational frequency of the flyback power converter is less than a predetermined frequency, and the input voltage is less than a predetermined voltage.

Control method of a flyback power converter

Asymmetric power converter includes an upper bridge switch, a lower bridge switch, a primary winding, a first secondary winding, a second secondary winding, a control circuit. The first secondary winding and the second secondary winding output a first output voltage and a second output voltage of a secondary side of the asymmetric power converter respectively, and voltage polarity of the first secondary winding is different from voltage polarity of the second secondary winding. The control circuit controls the lower bridge switch and the upper bridge switch according to the first output voltage and the second output voltage, respectively.

Asymmetric power converter and operational method thereof

A power factor correction (PFC) controller applied to a primary side of a power converter includes a feedback pin, a sensing pin, a current detecting circuit, an output voltage detecting circuit, and a determination circuit. The current detecting circuit is coupled to the feedback pin and the sensing pin for detecting an output current of a secondary side of the power converter according to a feedback voltage of the feedback pin and a sensing voltage of the sensing pin. The output voltage detecting circuit is coupled to the feedback pin for detecting an output voltage of the secondary side of the power converter according to the feedback voltage. The determination circuit is coupled to the current detecting circuit and the output voltage detecting circuit for turning on or turning off a PFC circuit coupled to the power converter according to the output current and the output voltage.

Power factor correction controller and operational method thereof

A power supply is configured to limit its output power, converting an input voltage on a primary side into a bus voltage on a secondary side. A current-sense resistor detects a bus current output from the power supply to provide a current-sense signal. A bus switch is electrically connected to a secondary winding on the secondary side, configured to selectively supply power to the bus voltage. A power delivery controller controls the bus switch in response to the current-sense signal and a power detection signal on the secondary side. The power delivery controller provides a power threshold in response to the bus voltage, compares the power detection signal with the power threshold, and turns off the bus switch to stop supplying power to the bus voltage if the power detection signal exceeds the power threshold, thereby limiting the output power of the power supply.

Power supplies with limited power protection and relevant control methods

A controller for extending a protection period of a power converter includes a delay circuit. The delay circuit is coupled to a supply voltage pin of the controller. When the power converter enters a protection mode, the delay circuit is enabled, receives a supply voltage through the supply voltage pin, and extends a protection period corresponding to the protection mode according to the supply voltage.

Controller for extending a protection period of a power converter and operational method thereof

A controller for increasing efficiency of a power converter includes a comparison module and a gate signal generation unit. The comparison module is used for generating a detection voltage according to a direct current (DC) input voltage of a primary side of the power converter, and comparing the detection voltage with a predetermined value to generate a comparison result. The gate signal generation unit is used for changing a sink current flowing through a gate pin of the controller according to the comparison result, wherein the gate pin of the controller is coupled to a power switch of the primary side of the power converter.

Controller for increasing efficiency of a power converter and a related method thereof

A synchronous rectifier applied to a secondary side of a power converter includes a forbidden turning-on time generation circuit, a green mode signal generation circuit, and a controller. The forbidden turning-on time generation circuit generates a forbidden turning-on time corresponding to the secondary side according to a synchronous signal of the secondary side. The green mode signal generation circuit enables a green mode signal when the forbidden turning-on time is greater than a reference value by at least one time, and disables the green mode signal when the forbidden turning-on time is continuously less than a reference value by a predetermined number of times. The reference value is changed with an output voltage of the secondary side. The controller enters a green mode when the green mode signal is enabled, and leaves the green mode when the green mode signal is disabled.

Synchronous rectifier applied to a secondary side of a power converter and operational method thereof

A multi-mode controller applied to a power converter includes a detection range generation module and a gate signal generation unit. The detection range generation module is used for generating a comparison voltage according to a reference current, and generating a detection signal according to the comparison voltage and a first reference voltage. When the detection signal is disabled by a zero-crossing signal, the gate signal generation unit generates a gate control signal corresponding to a quasi-resonant mode of the power converter according to the zero-crossing signal; and when the detection signal is disabled by a continuous-conduction mode signal generated by the detection range generation module according to the comparison voltage and a second reference voltage, the gate signal generation unit generates the gate control signal corresponding to a continuous-conduction mode of the power converter according to the continuous-conduction mode signal.

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Hsin-Chu, Taiwan

Ming-Chang Tsou