ADM8843

ADM8843 is a kind of four white LED backlight driver. ADM8843 uses charge pump technology to provide the power to drive up to four LEDs. The LEDs are used for back-lighting a color LCD display that has regulated constant current for uniform brightness intensity. The typical applications include cellular phones with main and sub displays, white LED backlighting, camera flash/strobes and movie light applications, micro TFT color displays, DSC and PDAs.

There are some features of ADM8843 as follows. First, it drives 4 LEDs from a 2.6 V to 5.5 V (Li-Ion) input supply. The second is 1*/1.5*/2* fractional charge pump to maximize power efficiency. Then is 0.3% typical LED current matching. Next is up to 88% power efficiency over Li-Ion range. Besides, it powers main and sub display LEDs with individual shutdown. The sixth is low power shutdown mode. The seventh is shutdown function. The last one is soft start limiting in-rush current.

What comes next is about the absolute maximum ratings of ADM8843(TA = 25, unless otherwise noted). The supply voltage (VCC) is from -0.3 to +6.0 V. The CTRL1, CTRL2 is from -0.3 to +6.0 V. The feedback Pins FB1 to FB4 is from -0.3 to +6.0 V. The operating temperature range is from -40 to +85. The storage temperature range is from -65 to +125. The power dissipation is 2 mW. Then is about the thermal characteristics. The JA is 50/W for 16-lead LFCSP (CP-16-3) package and 42.5/W for 16-lead LFCSP (CP-16-12) package.