US Pat. No. 9,271,347

TRIAC DIMMABLE LED DRIVER CIRCUIT

Shanghai Bright Power Sem...

1. A TRIAC dimmable LED driver circuit comprises an input AC voltage source connected to a rectifier bridge and an LED load,
the LED load is connected to an inductor or a transformer, a power MOS transistor, a low voltage MOS transistor and a current
sensing resistor, the inductor or transformer includes at least two windings, the first winding is connected to the power
MOS transistor, the auxiliary winding is connected to the positive terminal of a supplying diode, the negative terminal of
the supplying diode is connected to a supplying capacitor, the LED driver further includes two resistors and an over voltage
protection circuit, the resistors are in series and are connected to the auxiliary winding of the inductor or transformer,
and the middle point of the resistors are connected to the over voltage protection circuit, the LED driver is characterized
in that,
a peak current comparator, which is used to compare the voltage between the 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.

US Pat. No. 9,923,507

POSITION-SENSORLESS CONTROL METHOD AND APPARATUS FOR BRUSHLESS MOTOR

SHANGHAI BRIGHT POWER SEM...

1. A position-sensorless control method for a brushless motor, wherein the method comprises:
turning off a first driving voltage of a first phase coil, and within a detection time, detecting a back electromotive force
of the first phase coil;

determining a reference phase and a cycle of a second driving voltage according to the back electromotive force;
determining a pulse width modulation signal according to the reference phase and the cycle; and
determining to provide the second driving voltage for the brushless motor according to the pulse width modulation signal,
the second driving voltage being used to drive the brushless motor;

wherein:
the detection time comprises: blanking time and back electromotive force detection time;
the blanking time is time required by decreasing a phase current of the first phase coil to zero after the first driving voltage
is turned off; and

the back electromotive force detection time is time required by detecting the back electromotive force of the first phase
coil after the phase current of the first phase coil is decreased to zero.

US Pat. No. 9,107,260

CURRENT RIPPLE CANCELING LED DRIVER

Shanghai Bright Power Sem...

1. A current ripple canceling LED driver, comprising: an input source, a filtering capacitor and an LED load, characterized
in that,
the LED load is connected to 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,

wherein the input source is a current source containing a current ripple, the operational amplifier compares the voltage signal
across the current sensing resistor with a dynamic reference voltage, the dynamic reference voltage being a voltage signal
of an integrating capacitor, and the power switch is controlled to regulate the LED load current to be a nearly no ripple
DC current.

US Pat. No. 10,292,229

LINE VOLTAGE COMPENSATION CIRCUIT, LED DRIVE SYSTEM AND DRIVE METHOD

Shanghai Bright Power Sem...

1. A line voltage compensation circuit being configured to receive a signal reflecting bus voltage and output a line voltage compensation signal based on the received signal reflecting bus voltage, a preset baseline voltage and at least one reference voltage, wherein the line voltage compensation signal has a multi-segment linear relationship with the received signal reflecting bus voltage, the at least one reference voltage includes a first reference voltage, and the line voltage compensation circuit comprises:a first control signal generation module, configured to receive the first reference voltage and output a first control signal based on the first reference voltage; and
a line voltage generation module, electrically connected with the first control signal generation module, and configured to receive the signal reflecting bus voltage, the first control signal and the baseline voltage, and generate the line voltage compensation signal based on the received signal reflecting bus voltage, the first control signal and the baseline voltage.

US Pat. No. 10,772,170

TRIAC DIMMER DETECTION CIRCUIT, CHIP AND METHOD, AND LED DRIVING CHIP AND SYSTEM

SHANGHAI BRIGHT POWER SEM...

1. A dimmer detection circuit comprising:a sampling unit, coupled to output of a rectifier and configured to output a signal representing a bus voltage;
a first comparator coupled to the sampling unit and configured to receive a first reference voltage and the signal, and generate a first processing signal;
a second comparator coupled to the sampling unit and configured to receive a second reference voltage and the signal, and generate a second processing signal; and
a control unit configured to receive the first processing signal and the second processing signal to detect the slope of the bus voltage change from the first reference voltage to the second reference voltage; wherein
the control unit outputs a dimmer detection result which indicates a leading edge phase cut or a trailing edge phase cut dimmer is present or neither by detects falling edge or rising edge of the first processing signal and the second processing signal.