TI LP5521TM/NOPB

The LP5521 is a three-channel LED driver designed to produce variety of lighting effects for mobile devices. A 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 autonomously without processor control allowing power savings. The device maintains excellent efficiency over a wide operating range by automatically selecting proper charge pump gain based on LED forward voltage requirements and 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. The LP5521 has a flexible digital interface. Trigger I/O and a 32-kHz clock input allow synchronization between multiple devices. Interrupt output can be used to notify processor, when LED sequence has ended. The LP5521 has four pin selectable I²C-compatible addresses. This allows connecting up to four parallel devices in one I²C-compatible bus. GPO and INT pins can be used as a digital control pin for other devices. The LP5521 requires only four small, low-cost ceramic capacitors. Comprehensive application tools are available, including command compiler for easy LED sequence programming.

• 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-nA Typical Shutdown Current
• Automatic Power Save Mode
• I²C-Compatible Interface
• Independently Programmable Constant Current Outputs with 8-Bit Current Setting and 8-Bit PWM Control
• Typical LED Output Saturation Voltage 50 mV and Current Matching 1%
• Three Program Execution Engines with Flexible Instruction Set
• Autonomous Operation Without External Control
• Large SRAM Program Memory
• Two General Purpose Digital Outputs

• Fun and Indicator Lights
• LCD Sub-Display Backlighting Keypad RGB Backlighting and Phone Cosmetics
• Vibra, Speakers, Waveform Generator
• Blood Glucose Meter
• Handheld POS Terminals Electronic Access Control Where RGB Indication is Needed