LED dimmer circuit

Function module A8402 is used in voltage-frequency mode to provide controllable dimming of the LED display. Controllable dimming is achieved by changing the frequency of the blank input of the display driver . The display pulses on and off quickly, and the higher the duty cycle, the brighter the display becomes. When the input voltage reaches maximum, the converter is forced out of the linear region and the mono channel of the converter is always turned on for best display.