Abstract: Disclosed are a phase-tracked pulse generation circuit and a power supply device. The present application uses a driving pulse rising edge of a power supply as a reference, and uses a constant current circuit to charge a charging and discharging circuit at a constant current. When the reference driving pulse rising edge comes, the charging and discharging circuit is discharged; the peak voltage on the charging and discharging circuit is taken out and then divided for comparison with the voltage on the charging and discharging circuit; when the voltage on the charging and discharging circuit is equal to a divided voltage value of the peak voltage, the output of a comparison circuit turns high, and the output of a comparator is the phase-tracked pulse; the rising edge of the phase-tracked pulse can be used for synchronizing another power supply.

Abstract: Disclosed are a phase-tracked pulse generation circuit and a power supply device. The present application uses a driving pulse rising edge of a power supply as a reference, and uses a constant current circuit to charge a charging and discharging circuit at a constant current. When the reference driving pulse rising edge comes, the charging and discharging circuit is discharged; the peak voltage on the charging and discharging circuit is taken out and then divided for comparison with the voltage on the charging and discharging circuit; when the voltage on the charging and discharging circuit is equal to a divided voltage value of the peak voltage, the output of a comparison circuit turns high, and the output of a comparator is the phase-tracked pulse; the rising edge of the phase-tracked pulse can be used for synchronizing another power supply.

Abstract: An adjustment method for LED backlight brightness, comprising the following steps of: if the current LED backlight brightness is greater than a preset value, maintaining the PWM duty ratio as the maximum value, and adjusting the LED backlight brightness by adjusting an LED conduction current (S10); and if the current LED backlight brightness is not greater than the pre-set value, maintaining the LED conduction current to be constant, and adjusting the LED backlight brightness by adjusting the change of the PWM duty ratio between the maximum value and the minimum value (S20). This method can improve the light-emitting efficiency of LEDs, reduce backlight loss, and reduce the noise generated by an LED drive circuit.

Abstract: An adjustment method for LED backlight brightness, comprising the following steps of: if the current LED backlight brightness is greater than a preset value, maintaining the PWM duty ratio as the maximum value, and adjusting the LED backlight brightness by adjusting an LED conduction current (S10); and if the current LED backlight brightness is not greater than the pre-set value, maintaining the LED conduction current to be constant, and adjusting the LED backlight brightness by adjusting the change of the PWM duty ratio between the maximum value and the minimum value (S20). This method can improve the light-emitting efficiency of LEDs, reduce backlight loss, and reduce the noise generated by an LED drive circuit.