The LTC3220/LTC3220-1 are highly integrated multi-display LED drivers. These parts contain a high efficiency, low noise charge pump to provide power to up to eighteen universal LED current sources. The LTC3220/LTC3220-1 require only ?ve small ceramic capacitors to form a complete LED power supply and current controller. The LED currents are set by an internal precision current reference. Independent dimming, on/off, blinking and gradation control for all universal current sources is achieved via the I2C serial interface. 6-bit linear DACs are available to adjust brightness levels independently for each universal LED current source. The LTC3220/LTC3220-1 charge pump optimizes ef?ciency based on the voltage across the LED current sources. The part powers up in 1x mode and will automatically switch to boost mode whenever any enabled LED current source begins to enter dropout. The ?rst dropout switches the parts into 1.5x mode and a subsequent dropout switches the LTC3220/LTC3220-1 into 2x mode. The parts reset to 1x mode whenever a data bit is updated via the I2C port.