The LM27953 is a charge-pump-based white-LED driver that is ideal for mobile phone display backlighting. It is intended to drive 4 LEDs for a main phone display backlight. Regulated internal current sources deliver excellent current and brightness matching in all LEDs. The LED driver current sinks can be used to backlight a main phone display with up to 4 LEDs. The low-side current drivers accommodate common-anode-type LEDs. The current sinks can also drive standard two-terminal LEDs, and provide other general lighting functions (keypad lighting, fun lighting, etc). The brightness of the LEDs can be adjusted independently with an external resistor. The LM27953 works off an extended Li-Ion input voltage range (2.7V to 5.5V). Voltage boost is achieved with a high-efficiency 3/2×-gain charge pump. The LM27953 is available in National's chip-scale 18-bump micro SMD package.