LP5521 Datasheet | National Semiconductor

Description The LP5521 is a three channel LED driver designed to produce variety of lighting effects for mobile devices. High efficiency charge pump enables LED driving over full Li-Ion battery voltage range. The device has a program memory for creating variety of lighting sequences. When program memory has been loaded, LP5521 can operate independently without processor control. .. LP5521 maintains excellent efficiency over a wide operating range by automatically selecting proper charge pump gain based on LED forward voltage requirements. LP5521 is able to automatically enter power-save mode, when LED outputs are not active and thus lowering current consumption. Three independent LED channels have accurate programmable current sources and PWM control. Each channel has program memory for creating desired lighting sequences with PWM control. LP5521 has a flexible digital interface. Trigger I/O and 32 k Hz clock input allow synchronization between multiple devices. Interrupt output can be used to notify processor, when LED sequence has ended. LP5521 has four pin selectable I2C addresses. This allows connecting up to four parallel devices in one I2C bus. GPO and INT pins can be used as a digital control pin for other devices. LP5521 requires only four small and low cost ceramic capacitors. LP5521 is available in tiny 2.1x1.7x0.6 mm micro SMD-20 package and in 4.0x5.0x0.8 mm bumped LLP-24 package. prehensive application tools are available, including mand piler for easy LED sequence programming. Features - Adaptive charge pump with 1x and 1.5x gain provides up to 95% LED drive efficiency - Charge pump with soft start and overcurrent/short circuit - - - - - - - - - - - - - protection Low input ripple and EMI Very small solution size, no inductor or resistors required 200 n A typical shutdown current Automatic power save mode I2C patible interface Independently programmable constant current outputs with 8-bit current setting and 8-bit PWM control Typical LED output...