Abstract: The provided is a switching cycle adaptive control method for a switching power supply. The method includes: setting a voltage threshold for a bus voltage and forming voltage partitions; acquiring a bus voltage and determining the voltage partition to which the acquired bus voltage belongs; setting a power threshold for an output power of a switching power supply and forming power partitions; performing closed-loop control on a reference voltage and an output voltage of the switching power supply and determining the power partition to which the acquired output power belongs; setting different reference valley numbers P; setting different power valley numbers Q; determining a real-time reference valley number P and a real-time power valley number Q; adding the reference valley number P and the power valley number Q to obtain the number of valleys; and adjusting the frequency of a PWM signal of the switching power supply.

Abstract: An LED backlight driving circuit with a voltage regulating unit is provided. The LED backlight driving circuit includes a power supply unit, an LED string, an ADC voltage detection circuit, and a driving controller; the ADC voltage detection circuit is used to detect a voltage value Vled of a negative terminal of a LED string, and the ADC voltage detection circuit includes an ADC sampling module that converts the measured voltage value Vled at the negative terminal of the LED string into a voltage numerical code; for the numerical code of the negative terminal voltage value Vled measured by the ADC sampling module, a first threshold V1 and a second threshold V2 are set.

Abstract: An LED backlight driving circuit based on low-potential-end switch control and a backlight driving method are provided. The LED backlight driving circuit includes a plurality of LED strings, a channel control switch device, a constant current module, a channel switching control module, a signal control unit, and an SPI interface unit. Each of the LED strings has a high-potential-end directly connected to an LED driving voltage VLED and a low-potential-end connected to one channel control switch device and one constant current module, and a plurality of channel control switch devices in each group of LED strings are connected to one channel switching control module; and the channel switching control module is used to control the on-state duty cycle of the LED strings in the group.

Abstract: An LED backlight driving circuit based on low-potential-end switch control and a backlight driving method are provided. The LED backlight driving circuit includes a plurality of LED strings, a channel control switch device, a constant current module, a channel switching control module, a signal control unit, and an SPI interface unit. Each of the LED strings has a high-potential-end directly connected to an LED driving voltage VLED and a low-potential-end connected to one channel control switch device and one constant current module, and a plurality of channel control switch devices in each group of LED strings are connected to one channel switching control module; and the channel switching control module is used to control the on-state duty cycle of the LED strings in the group.

Abstract: An LED backlight driving circuit with a voltage regulating unit is provided. The LED backlight driving circuit includes a power supply unit, an LED string, an ADC voltage detection circuit, and a driving controller; the ADC voltage detection circuit is used to detect a voltage value Vled of a negative terminal of a LED string, and the ADC voltage detection circuit includes an ADC sampling module that converts the measured voltage value Vled at the negative terminal of the LED string into a voltage numerical code; for the numerical code of the negative terminal voltage value Vled measured by the ADC sampling module, a first threshold V1 and a second threshold V2 are set.

Abstract: A light-emitting diode (LED) backlight modulation method based on duty cycle reference point setting is provided, and the LED backlight modulation method is applied to an LED backlight control circuit with row and column scan lines. Different duty cycle reference points are set for the LED string channels in the LED backlight control circuit in row-column scanning mode, whereby the LED string channels can be turned on or off at different time points during a turn-on duration of the row scan line to achieve lighting in the duty cycle, so as to realize the staggered setting of the turn-on time point and turn-off time point of each channel and avoid the need for large current jump at a power drive terminal.

Abstract: A light-emitting diode (LED) dimming driving device includes a digital-to-analog converter (DAC) control signal generating unit and an LED driving signal generating unit. The DAC control signal generating unit generates a first control signal and a second control signal. The first control signal is input to the LED driving signal generating unit to generate a first driving current I1, and the second control signal is input to the LED driving signal generating unit to generate a second driving current I2. The first driving current I1 is less than a maximum power current value Ipeak corresponding to a peak power of the LED driving signal generating unit, and the second driving current I2 is greater than the maximum power current value Ipeak corresponding to the peak power of the LED driving signal generating unit.

Abstract: A backlight LED driver circuit with current regulating function is provided. The backlight LED driver circuit includes: a LED light-emitting element, a first transistor, a first amplifier, a current regulator module, and a voltage regulator module; the current regulator module including a plurality of current channels, each including one second transistor and one third transistor; the voltage regulator module including a fourth transistor, a fifth transistor, and a sixth transistor; the fourth transistor, the fifth transistor, and the sixth transistor in the voltage regulator module and the second transistor and one third transistor of each of the current channels in the current regulator module constitute a current mirror; and the current regulator module further including a decoder configured to generate a signal for controlling on and off states of the plurality of second transistors in the plurality of current channels in response to an input digital control signal.

Abstract: A current sampling circuit with on-chip real-time calibration is used to detect the on-state current of a driving transistor. The current sampling circuit includes a first resistor, a second resistor, a voltage sampling circuit, a sampling voltage operational circuit and an on-state resistance calibration circuit. The voltage sampling circuit is used to obtain on-state voltage drop value of the driving transistor Vds. The on-state resistance calibration circuit includes a reference current source and a calibrating transistor. On-state resistance value of the calibrating transistor is set to be K1 times of on-state resistance value of the driving transistor. The on-state voltage drop value Vds obtained by the voltage sampling circuit and the on-voltage drop value of the calibrating transistor Vrsns are input to the sampling voltage operational circuit to obtain proportional relationship K2 between the on-state voltage drop value Vds and the on-state voltage drop value Vrsns.

Abstract: A backlight LED driver circuit with current regulating function is provided. The backlight LED driver circuit includes: a LED light-emitting element, a first transistor, a first amplifier, a current regulator module, and a voltage regulator module; the current regulator module including a plurality of current channels, each including one second transistor and one third transistor; the voltage regulator module including a fourth transistor, a fifth transistor, and a sixth transistor; the fourth transistor, the fifth transistor, and the sixth transistor in the voltage regulator module and the second transistor and one third transistor of each of the current channels in the current regulator module constitute a current mirror; and the current regulator module further including a decoder configured to generate a signal for controlling on and off states of the plurality of second transistors in the plurality of current channels in response to an input digital control signal.

Abstract: A light-emitting diode (LED) dimming driving device includes a digital-to-analog converter (DAC) control signal generating unit and an LED driving signal generating unit. The DAC control signal generating unit generates a first control signal and a second control signal. The first control signal is input to the LED driving signal generating unit to generate a first driving current I1, and the second control signal is input to the LED driving signal generating unit to generate a second driving current I2. The first driving current I1 is less than a maximum power current value Ipeak corresponding to a peak power of the LED driving signal generating unit, and the second driving current I2 is greater than the maximum power current value Ipeak corresponding to the peak power of the LED driving signal generating unit.

Abstract: A current sampling circuit with on-chip real-time calibration is used to detect the on-state current of a driving transistor. The current sampling circuit includes a first resistor, a second resistor, a voltage sampling circuit, a sampling voltage operational circuit and an on-state resistance calibration circuit. The voltage sampling circuit is used to obtain on-state voltage drop value of the driving transistor Vds. The on-state resistance calibration circuit includes a reference current source and a calibrating transistor. On-state resistance value of the calibrating transistor is set to be K1 times of on-state resistance value of the driving transistor. The on-state voltage drop value Vds obtained by the voltage sampling circuit and the on-voltage drop value of the calibrating transistor Vrsns are input to the sampling voltage operational circuit to obtain proportional relationship K2 between the on-state voltage drop value Vds and the on-state voltage drop value Vrsns.

Abstract: A light-emitting diode (LED) backlight modulation method based on duty cycle reference point setting is provided, and the LED backlight modulation method is applied to an LED backlight control circuit with row and column scan lines. Different duty cycle reference points are set for the LED string channels in the LED backlight control circuit in row-column scanning mode, whereby the LED string channels can be turned on or off at different time points during a turn-on duration of the row scan line to achieve lighting in the duty cycle, so as to realize the staggered setting of the turn-on time point and turn-off time point of each channel and avoid the need for large current jump at a power drive terminal.