Shanghai Bright Power Semiconductor Co., Ltd.

Bright Power Semiconductor, Inc.

Shungen Sun

Liqiang Hu

Xiaoru Gao

Weijia Yu

Hanfei Yang

Xiaohui Cai

Zhen Zhu

He Huang

Yihui Chen

Rulong Jiang

Hong Zhang

Fuqiang Zhang

Pengfei Lu

Deshui Yu

A control circuit for a switched-mode power converter to generate a control signal for controlling switching transistors in the power converter is disclosed. The control circuit includes: a comparator; a ramp compensation circuit for producing and applying a ramp compensation signal to a first or second input of the comparator; an on-time generation circuit to generate an on-time timer signal; and a control signal generation circuit to generate, based on the comparison signal and the on-time timer signal, the control signal for controlling the switching transistors in the power converter. The ramp compensation signal output from the ramp compensation circuit is configured with: a first slope during an inductor demagnetization interval in operation of the power converter in CCM and a second slope during an inductor demagnetization interval and a zero-current interval in operation of the power converter in DCM, the first slope is greater than the second slope.

Power converter and control circuit thereof

A high power factor control circuit is disclosed, which is used in an AC/DC converter. The converter includes a rectification module, a conversion module and a load. The rectification module receives AC power and rectifies it into a DC current, and the conversion module converts the DC current to drive power as desired by the load and provides it to the load. The conversion module includes a conversion element including an inductive element and a switching element. The control circuit includes a peak limiting signal generator and a switching element control module. The peak limiting signal generator receives a reference signal and produces at least one peak limiting signal from a sample signal. The switching element control module is configured to control switching of the switching element so that, within at least half a line-frequency period, a value of the ripple in the output current flowing through the load is not greater than a limit value.

Control circuit with high power factor and AC/DC converter

A control circuit for a power converter is disclosed. The power converter includes a switching circuit including a first switching transistor and a second switching transistor. The control circuit includes: a comparator having a first input configured to receive at least a reference signal, a second input configured to receive at least a feedback signal and an output configured to output a comparison signal; a minimum off-time generation circuit; an on-time generation circuit for producing an on-time signal for controlling both the first switching transistor and the second switching transistor; and a ramp compensation circuit configured to generate a ramp compensation signal.

The present application provides a color LED driving circuit, which comprises a set of switches and a color controller. The switch assembly has a first switch and a second switch, respectively having a first terminal, a second terminal and a control terminal. The first terminal of the first switch is configured to be coupled to a first LED load, and the first terminal of the second switch is configured to be coupled to a second LED load. The color controller comprises a first controller and a second controller. A ground terminal of the first controller is coupled to ground. The first controller is used to generate an output signal according to a PWM signal, and transmit the output signal to the second controller. The second controller is used to generate a first driving signal and a second driving signal according to the output signal, and output the first driving signal and the second driving signal to the control terminals of the first switch and the second switch through a first driving terminal and a second driving terminal, respectively. A reference terminal of the second controller is coupled to the second terminal of the first switch and the second terminal of the second switch, and potential of the reference terminal is different from a potential of the ground terminal of the first controller.

Color LED driving circuit and color controller

A switch-mode power supply (SMPS), an SMPS system and a power supply method for an SMPS system are disclosed. The SMPS controller includes an output-voltage power supply unit, a built-in energy storage unit and a logic control unit. The output-voltage power supply unit is configured to charge the built-in energy storage unit using an output voltage from the SMPS system so that the built-in energy storage unit can provide an operating voltage for the logic control unit. The use of a stand-off energy storage capacitor can be dispensed with, and the use of the output voltage as a power supply is enabled. As a result, significant reductions in overall and standby power dissipation are achieved. In addition, the SMPS controller may further include a high-voltage power supply unit, which provides a hybrid power supply solution, together with the output-voltage power supply unit.

Switch-mode power supply (SMPS) controller, SMPS system and power supply method for SMPS system

A control circuit for a constant-current drive circuit, as well as a constant-current drive circuit are disclosed. The control circuit can obtain output information of the constant-current drive circuit and use it in combination with reference information to determine, according to an output condition corresponding to the current load of the constant-current drive circuit, a time point for the system to enter or exit a rapid drive mode. Therefore, it can be suitably used in various application scenarios to determine a time point for the system to entry into or exit from the rapid start mode. Compared with fast charging for a fixed period of time as used in the prior art, embodiments of the present invention can effectively overcome the problem of easy overshooting or inadequate acceleration during start as found in various applications.

Control circuit for constant-current drive circuit and constant-current drive circuit

A control circuit, a chip and a control method are disclosed. The control circuit includes: an adjustment signal generation unit configured to detect an electrical signal reflecting a power supplied to a load under control of a current value of a reference signal, generate a feedback signal and output an adjustment signal based on both the feedback signal and the reference signal; and a control unit coupled to the adjustment signal generation unit and configured to control the switching circuit on and off based on the adjustment signal. With the generated adjustment signal that reflects a change in an adjustment metric indicated in the reference signal, the control circuit and the driving system can be adapted in real time to the specifications of any AC power standard. Moreover, much more granular adjustments can be made in the power supplied to the load.

Control circuit, chip and control method

A control circuit for a power converter comprising switching transistors and an output inductor is disclosed. One terminal of the output inductor serves as an output node, and another terminal of the output inductor serves as a switching node. The control circuit is configured to generate a control signal for controlling switching transistors in the power converter. The control circuit includes: a RC oscillator network connected to two terminals of the output inductor, the RC oscillator network configured to generate an oscillation signal containing a feedback ramp slope compensation component in response to a change in a voltage across the terminals of the output inductor; a comparator; an on-time generation circuit; and a control signal generation circuit to generate the control signal for controlling the switching transistors in the power converter.

Multiphase power processing circuit and a method for control thereof are disclosed, with which, exchange of data is achievable between a multiphase controller and any of power processing circuits via pins of at least two of the three categories, Enable, PWM and Temperature Indicator, of the multiphase controller. The exchanged data may include, but is not limited to, a phase identifier, an over-current protection threshold, an over-current protection threshold, an over-temperature protection threshold, a current sampling gain, a current sampling bias, a temperature sampling gain, a temperature sampling bias, a drive speed and the like of the power processing circuit. In this way, improvements in system flexibility and security are obtained.

Multiphase power processing circuit and method for control thereof

The present disclosure provides a leakage protection circuit, a method and a drive device. The leakage protection circuit is used for being electrically connected with the power supply line of a load, and may be configured to sample the power supply line at intervals, detect the voltage of the sampled electrical signals to determine whether the voltage of the AC input power is divided, and provide leakage protection based on the determined result. The present disclosure can prevent human from electric shock through sampling the electric signals from the power supply line at intervals and performing voltage detection and comparasion to determine whether the voltage of the accessed AC input power is divided, when the voltage of the accessed AC input power is determined to be divided, the power supply line will be controlled in non-conductive state.

Leakage protection circuit, method and drive device

The present disclosure provides a leakage protection circuit, a method and a drive device. The leakage protection circuit is used for being electrically connected with the power supply line of a load, and may be configured to sample the power supply line at intervals, detect the voltage of the sampled electrical signals to determine whether the voltage of the AC input power is divided, and provide leakage protection based on the determined result. The present disclosure can prevent human from electric shock through sampling the electric signals from the power supply line at intervals and performing voltage detection and comparison to determine whether the voltage of the accessed AC input power is divided, when the voltage of the accessed AC input power is determined to be divided, the power supply line will be controlled in non-conductive state.

A TRIAC dimmable light-emitting diode (LED) driver circuit is disclosed, compromising: An alternating-current (AC) voltage connected to a rectifier bridge; An LED load, which is connected to an inductor or a transformer, a power MOS transistor, a low voltage MOS transistor and a current sensing resistor. The LED driver also compromises: a peak current comparator which is used to compare the voltage between a current sensing resistor and a reference voltage; a maximum on-time timer, which is used to detect the on time of the low voltage MOS transistor. When the voltage on the current sensing resistor is higher than the reference voltage or the on time of the low voltage MOS transistor reaches the preset time of the maximum on-time timer, the low voltage MOS transistor is turned off.

TRIAC dimmable LED driver circuit

A current ripple canceling light-emitting diode (LED) driver is disclosed. The input current source contains a current ripple. The LED load is connected to the drain of a power switch. The source of the power switch is connected to a current sensing resistor. The gate of the power switch is connected to the output of an operational amplifier. The operational amplifier compares the voltage signal across the current sensing resistor with a dynamic reference voltage. The dynamic reference voltage is adjusted according to the gate or drain voltage of the power switch. The LED load current is controlled to be a nearly no ripple DC current.

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Shanghai, China

Shungen Sun