AAT1231-1

Step-Up DC/DC Converters for White LED Backlight Applications General Description The AAT1231/1231-1 are high frequency, high efficiency constant current boost converters capable of 24V maximum output voltage. Both devices are ideal power solutions for backlight applications with up to six white LEDs in series or up to twelve white LEDs in a parallel/series configuration. The input voltage is 2.7V to 5.5V for single-cell lithiumion/polymer (Li-ion) based portable devices. The LED current is digitally controlled across a 6x operating range using AnalogicTech’s Simple Serial Control™ (S2Cwire™) interface. Programmability across 26 discrete current steps provides high resolution, low noise, flicker-free, constant LED outputs. In programming AAT1231 operation, LED brightness increases based on the data received at the EN/SET pin. In programming AAT1231-1 operation, LED brightness decreases based on the data received at the EN/SET pin. The SEL logic pin changes the feedback voltage between two programmable ranges. AAT1231/1231-1 SwitchReg™ Features The AAT1231 and the AAT1231-1 feature high current limit and fast, stable transitions for stepped or pulsed www.DataSheet4U.com current applications. The high switching frequency (up to 2MHz) provides fast response and allows the use of ultra-small external components, including chip inductors and capacitors. Fully integrated control circuitry simplifies design and reduces total solution size. The AAT1231 ...