Monolithic Power Systems, Inc.

Chengdu Monolithic Power Systems Co., Ltd.

Joulwatt Technology (hangzhou) Co., Ltd.

Joulwatt Technology Inc. Limited

Yuancheng Ren

Junming Zhang

Xunwei Zhou

Pitleong Wong

Lei Du

Naixing Kuang

Eric X Yang

Siran Wang

En Li

Kaiwei Yao

Wei P Chen

Siopang Chan

Qian Ouyang

Lei Miao

Guoqiang Liu

Bo Yu

Yike Li

Feng Xu

Yiqing Jin

Bairen Liu

Yunping Lang

Jin Hu

Zhaoqi Mao

James Copland Moyer

Yang Shi

Min Xu

Bin Liu

Yang Lu

Zhijiang Yang

Kun Yi

Yingyan He

Xiaoli Kong

Yue Ji

Lang Bai

Biliang Huang

Peng Xu

Lijie Jiang

Michael Ren Hsing

Xiaokang Wu

Suhua Luo

Zheng Luo

Sicong Lin

Jiali Cai

Hao Long

Huanyu Lu

Zilin Fan

Xiaoqing Li

Zhijun Ye

Xiaoming Li

Xiaopeng Dong

Yang Cheng

Jiaqi Yu

Zhengui Bai

Yong Huang

Jielin Zhang

Libin Huang

Zhongwu Wu

Ken Yi

Miao Lei

ZhengXing Li

Zhishun Li

Bai Lang

Disclosed a drive method, a drive circuit for a power switch and a power supply system. During the turning-on period of the power switch, which can be roughly divided into three processes, a current limiting module is used to limit the current flowing through the power switch for preventing current overshoot, a logic control module is used for controlling the current limiting module not to operate before the turning-on period and the control terminal of the power switch is turned off; during the turning-on period, a feedback circuit adjusts the gate voltage of the power switch for controlling the current flowing through the power switch to reach a predetermined limited value quickly and then maintain at the limited value until the power switch is fully turned on. The current limiting module can be employed in various embodiments. According to the disclosure, the current flowing through the power switch can be effectively controlled during the turning-on period, and the driving time for turning on the power switch is decreased.

Drive method and drive circuit for power switch, and power supply system

A circuit and a method for detecting a current zero-crossing point, and a circuit and method for detecting a load voltage are disclosed. The circuit for detecting current zero-crossing point includes: a load power supply circuit, a voltage-dividing resistor, a transistor switch, a zero-crossing detection circuit; the load power supply circuit includes: a load, a diode, and a transformer; one end of a primary winding of the transformer is connected with the operating voltage input terminal, the other end of the primary winding of the transformer is connected with a first end of the transistor switch and a first end of the voltage-dividing resistor, a second end of the voltage-dividing resistor and a second end of the transistor switch are connected with the ground, the load voltage is controlled by the transistor switch.

Circuit and method for detecting current zero-crossing point and circuit and method for detecting load voltage

Disclosed a control circuit for a lighting circuit. In the control circuit, an AC input signal provided at an AC input terminal is rectified to obtain a rectified voltage, a low potential end of the rectified voltage is used as a reference ground, a load of the lighting circuit is composed of N strings connected in series, and N is a natural number greater than or equal to 2, when the control circuit detects that the AC input terminal is connected to a dimmer, the control circuit controls the N strings to be simultaneously turned on, when the control circuit detects that the AC input terminal is not connected to the dimmer, the control circuit controls the N strings to be individually turned on in accordance with the rectified voltage. According to the present disclosure, the lighting circuit can obtain a high power factor and is compatible with the dimmer, and the scheme is simple and easy to implement.

Control circuit and control method for lighting circuit, and lighting circuit

A protection circuit and an illumination driving circuit are described herein. The protection circuit comprises a detection circuit, detecting a current flowing through a first switch to obtain a current detection signal and determining whether there is leakage at an input terminal according to the current detection signal; a control circuit, controlling the first switch to switch on intermittently, detecting the current flowing through the first switch by the detection circuit during a switch-on period of the first switch, and keeping the load at a disconnection state if the detection circuit determines there is leakage; and the first switch, connected to the input terminal, and a control terminal of the first switch being connected to the control circuit, and the first switch being controlled by the control circuit to be switched on intermittently. The present invention has the protection function and enhances safety during load removing and installation processes.

Protection circuit and illumination driving circuit

The present invention provides a synchronous rectification control circuit, a method and a flyback switching circuit. A drive circuit outputs a drive signal to control the turn-on and turn-off of a synchronous rectification transistor; a threshold comparison circuit controls the drive circuit to output a pull-up drive signal to turn on the synchronous rectification transistor when a drain-source voltage is lower than a preset low threshold voltage and controls the drive circuit to output a pull-down drive signal to turn off the synchronous rectification transistor when the drain-source voltage is higher than or equal to a preset high threshold voltage; a voltage regulation control circuit controls the drive circuit to output a drive signal for pulling up a voltage of the drive signal to a preset pull-up voltage high value when the drain-source voltage is lower than a preset voltage regulation reference value.

Synchronous rectification control circuit, method and flyback switch circuit

A circuit and a method for detecting a current zero-crossing point, and a circuit and method for detecting a load voltage are disclosed. The circuit for detecting current zero-crossing point includes: a load power supply circuit (), a voltage-dividing resistor (), a transistor switch (), a zero-crossing detection circuit (); the load power supply circuit () includes: a load (), a diode (), and an inductor (); one end of the load power supply circuit () is connected with the operating voltage input terminal, the other end of the load power supply circuit () is connected with a first end of the transistor switch () and a first end of the voltage-dividing resistor (), a second end of the voltage-dividing resistor () and a second end of the transistor switch () are connected with the ground, the load voltage is controlled by the transistor switch (), the voltage-dividing terminal of the voltage-dividing resistor () is connected to a signal input terminal of the zero-crossing detection circuit (), the zero-crossing detection circuit () is used to determine whether the current of the diode () crosses zero to obtain the on time of the diode (), and the circuit for detecting load voltage uses the on time of the diode () and the on time of the transistor switch () to obtain the load voltage. The circuits are simple, but with high detection efficiency and low cost.

Circuit and method for detecting current zero-crossing point, and circuit and method for detecting load voltage

The present disclosure relates to a circuit and a method for overcurrent control and a power supply system including the same. When the system operates normally, a reference voltage has a constant value. When a short circuit or an overcurrent occurs at an output of the system, the reference voltage will be pulled down,. When the system is recovered from the short circuit or the overcurrent state, the reference voltage increases slowly up to a steady value. A feedback signal of an output voltage follows the reference voltage and increases slowly. Thus, an overshoot of the output voltage can be effectively eliminated to avoid damages to the system.

Circuit and method for overcurrent control and power supply system including the same

A power supply protection circuit and a method is described herein. The power supply protection circuit comprises a current control unit, a voltage feedback unit, and a current pull-up unit. The voltage feedback unit is connected to the current control unit, the voltage feedback unit obtains a feedback voltage of an output voltage and feeds back the feedback voltage to the current control unit, and the current control unit uses the feedback voltage to control the current control unit to regulate an output current. The current pull-up unit is connected to a feedback terminal of the voltage feedback unit, and the current pull-up unit provides the voltage feedback unit with a pull-up current to determine whether the feedback terminal of the voltage feedback unit is short-circuited.

Power supply protection circuit and method

The present invention provides a control circuit and a control method for a switch circuit and a switching-mode power supply circuit. The control method comprises following steps: detecting an output voltage or an output current, and adjusting an upper limit value and a lower limit value of an inductor current according to a result of comparing the output voltage or the output current with the corresponding reference; and sampling the inductor current, and controlling a main switch transistor in the circuit to be switched off when a sampling current rises to the upper limit value, and controlling the main switch transistor to be switched on when the sampling current drops to the lower limit value. In the present invention, the inductor current is fast in response without overshoot, the output voltage drops very little, there is no overshoot in a process of voltage recovery, and circuit transient response is fast.

Control circuit and control method for switch circuit and switching-mode power supply circuit

There is provided a dimming circuit, a dimming method and a LED driving circuit. On the basis of the dimming of a dimmer, the circuit according to the disclosure generates a plurality of current reference signals corresponding to a plurality of loads in accordance with a dimming signal, to change a ratio of load currents of the plurality of loads, so that, the adjustment of color temperature is implemented, wherein the dimming signal represents the changes of switching operation or dimming speed of the dimmer, and the ratio of current load currents of the plurality of loads is latched or a predetermined ratio of load currents is latched. According to the disclosure, the dimmer can be used for directly adjusting color temperature, without the need for a MCU, so that, the system compatibility is improved and the cost is decreased.

Dimming circuit, dimming method and LED driving circuit

A control method, a control circuit and a device for a switching circuit are disclosed, for fixing a frequency of the switching circuit when the switching circuit is operated under CCM. The present disclosure is suitable to various switching circuits, and an application scope of the control method of the switching circuit can be extended. The control method comprises: starting measuring time at a rising edge of a turn-on signal of the first switch; reducing a turn-on time or a turn-off time of the first switch when a first measured time is reached, and the rising edge in a next cycle of the turn-on signal has not arrived; increasing the turn-on time or the turn-off time of the first switch when the rising edge in the next cycle of the turn-on signal arrives but the first measured time is not reached.

Control circuit and device with edge comparison for switching circuit

The present invention provides a control method and a control circuit for a switch circuit and a corresponding switch circuit device. The control circuit comprises: an acquiring module, configured to acquire first time; a comparing module, connected with the acquiring module and configured to compare first time with first fixed time; and an adjusting module, connected with the comparing module. The adjusting module adjusts a cycle of a turn-on signal of a first switch transistor to second fixed time when the first time is less than the first fixed time. The adjusting module adjusts the sum of second time and the first fixed time to the second fixed time to achieve spread spectrum when the first time is more than the first fixed time. The control circuit for the switch circuit provided by the present invention is used for controlling the switch circuit for spread spectrum.

Control method and control circuit for switch circuit and switch circuit device

For controlling a switch power supply, an adjustment module produces a first control voltage by comparing a period of a switch signal with a reference period. A current source module generates a first charging current according to the first control voltage. A pulse signal generating module converts the first charging current into an on time signal or off time signal of a switch transistor. A driving module produces the switch signal according to the on time or off time signal of the switching transistor, so as to control the turn on and turn off signal of a switching transistor. A time measurement module obtains a time parameter according to the switch signal, and generates a periodic adjustment signal according to the time parameter. The adjustment module adjusts the reference period according to the periodic adjustment signal to adjust the period of the switch signal.

Control circuit and control method for switch power supply, and switch power supply

This invention provides a switch control circuit and a switch circuit. When a main transistor on-time reaches a constant on-time, whether an inductor current reaches an instruction current is detected; if the inductor current fails to reach the instruction current, the main transistor on-time is prolonged; the main transistor is turned off and the auxiliary transistor is turned on until the inductor current reaches the instruction current or exceeds the instruction current by a certain threshold; when the main transistor is turned off and the auxiliary transistor is turned on, the inductor current is detected in real time to check whether the inductor current is smaller than the instruction current, and the auxiliary transistor is turned off and the main transistor is turned on again if yes.

Switch control circuit and switch circuit

The present invention discloses a bleeder circuit; solutions of the present invention may be applied in linear driving and switch driving solutions; a threshold voltage is a zero crossing value, and when the input voltage is zero crossing, the load current at this time is zero; a bleeder current is generated to make the input current greater than a holding current of a TRIAC dimmer, to maintain turning-on of the TRIAC dimmer, and a second time is set as a delay time, which reduces power consumption. In the application of switch driving solution, the current regulating circuit is controlled to be enabled according to the waveform features of the previous and latter halves of periods of the sine wave as well as the size of the input current of the driving circuit. The present invention reduces bleeder current, improves system efficiency and system reliability while ensuring the dimming performance; meanwhile, it is good for enlarging the maximum turning-on angle of TRIAC, and satisfies the requirement for maximum output current more easily.

Bleeder circuit

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Hangzhou, China

Yuancheng Ren