LCD backlight Power Supply Selection

 

In the past two days, we have selected a 4.3-inch LCD screen for the fs_s5pc100 development platform of our R & D center. Finally, the a043fw02 V0 of Auo is set in many screens. I thought that the units that sold the screen could provide reference backlight images, but most of the results were not. A customized backlight can be provided, but it is expensive. Select your own power supply.

LCD backlight requirements:

 

Finally, we decided to use amessen's LED driver power chip cat4238. It is a TSOT23-5 package that supports 10 LEDs. The price is also relatively low. The wiring is as follows:

The principle is that the resistance of R1 can be used to control the current. The chip uses the feedback circuit to control the voltage of the FB end to 300mV. For example, if the LCD backlight requires 20mA of the current, select R1 as 15 euro. Because the current flowing through R1 is very small, you don't have to worry about the problem of R1 fever.

Verify the actual effect.