DATASHEET To request the full datasheet, please visit www.intersil.com/products/isl97901 RGB Buck-Boost Four-Channel LED Driver with Color Sequencing and Automatic White Balance ISL97901 Features The ISL97901 is a highly efficient four channel, 1.5A sequential LED driver powered from a single-cell Li-ion battery, or regulated input voltage up to 5.5V. The ISL97901 incorporates an independent current controlled driving mechanism for each of the LED's to allow accurate brightness control. • Buck-Boost Based LED Driver The ISL97901 also utilizes a buck-boost converter to ensure optimum output voltage is maintained for a wide variety of LED forward voltages. The ISL97901's highly integrated and efficient power conversion core operates at well over 90% efficiency across a wide range of operating conditions. The power conversion core implements a proprietary algorithm that allows seamless transitions and glitch-free operation between the buck and the boost modes as the battery voltage drops during operation. • Closed-Loop White Balancing Dynamic Current Scaling The ISL97901 provides I/O pins to interface with Intersil's optical sensor IC's for white balance control. White balance is achieved by closing the opto-electrical loop which allows for LED light output to get calibrated against preset target values. The ISL97901 can also be configured to run in an open-loop manner if real-time white balance control is not desired. In this case, the LED currents are set by the internal registers. • Dynamic Headroom Management • RGB, RGGB or RGBW Color Sequencing • Up to 1.5A Output Current • Photo Detector Feedback Interface • Dual Green LED Drive Support • Standby Current less than 70µA • I2C Interface • 150mV Feedback Voltage Reference for Current Regulation to Maximize Efficiency • 2.5MHz Switching Frequency • Programmable Output Voltage for each LED • Internal Current Setting Registers • Ambient Temperature Range: 0°C to +70°C • Pb-Free (RoHS Compliant) Applications • LED-Based Pico Projector In Mobile Phones Related Literature • Stand Alone Pico Projectors • ISL58333 “Wide Optical Spectrum Photo Sensor IC” • Tri-Stimulus Display Drivers • ISL58344 “Quad Segment Photo Sensor IC” C1 20-40µF 2.7V TO 4.3V Batt C3 1.0µF ENABLE VCC PGND CEN D1 EN1 D3 EN2 D4 DISABLE LCoS OR DLP DRIVER ASIC EN4 ISL97901 SCL SGND LFBP LFBN LED4 WHITE OR nd 2 GREEN FB1 FB2 CBYP SDA C2 47µF D2 EN3 C4 0.1µF LED3 VOUT VOUT LED2 VIN VIN LED1 2.2µH LX2 LX1 • Other Handheld Display Drivers RSNS 0.1 RSNS 0.1 PGND SDA SCL ADDR SENSOR PHOTO DETECTOR ISL58333 FIGURE 1. TYPICAL APPLICATION June 29, 2012 FN7824.0 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas Inc. 2012. All Rights Reserved Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries. All other trademarks mentioned are the property of their respective owners. ISL97901 For additional products, see www.intersil.com/product_tree Intersil products are manufactured, assembled and tested utilizing ISO9001 quality systems as noted in the quality certifications found at www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com Submit Document Feedback 2 FN7824.0 June 29, 2012