RT4532WSC Richtek

RT4532 High Efficiency Backlight LED Driver General Description Features Input Voltage Range : 2.5V to 5.5V The RT4532 is a high-efficiency LED driver for backlight Internal Schottky Diode applications. An asynchronous boost converter with an 2 Fast-speed mode I C Compatible Interface internal Schottky diode and a current source driver are Drive Up to 6 WLEDs in 4 String designed to support 6LED/channel with wide input voltage External PWM Brightness Control range from 2.5V to 5.5V. 550k/1.1MHz Switching Frequency 2 An I C interface can provide easy backlight control in fast Built-in Internal Soft-Start and high speed mode. The RT4532 supports linear 2 I C Programmable 256 Steps Linear Current mappings with 256 steps to setup the brightness of Regulation backlight LEDs. It also supports PWM dimming to adjust Up to 85% Efficiency with Small Magnetics the brightness. Programmable 16V/24V OVP The RT4532 provides complete protection functions such Current Accuracy 5% and Current Balance 3% as input under-voltage lockout, over-current, output over- UVLO, OVP, OCP, OTP Protection voltage and over-temperature protection. The OVP Shutdown Current : < 1A threshold voltage can be set at 16V and 24V for different Temperature Range : 40C to 85C applications. The RT4532 is available in the WL-CSP-10B 0.87x2.07 package. Applications Cellular Phones Ordering Information Digital Cameras RT4532 PDAs and Smart Phones Package Type Portable Instruments WSC : WL-CSP-10B 0.87x2.07 (BSC) Note : Richtek products are : RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. Simplified Application Circuit RT4532 L LX VOUT V OUT C OUT V IN VIN C IN x 6 Enable EN PWM SCL SDA FB1 GND FB2 Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS4532-00 May 2015 www.richtek.com 1RT4532 Pin Configurations Marking Information (TOP VIEW) 2K : Product Code W : Date Code 2KW A1 A2 LX GND VOUT B1 B2 VIN C1 C2 PWM EN SDA D1 D2 SCL E1 E2 FB2 FB1 WL-CSP-10B 0.87x2.07(BSC) Functional Pin Description Pin No. Pin Name Pin Function A1 LX Switch Node of Boost Converter. Connect an inductor between LX and VIN. Ground. The exposed pad must be soldered to a large PCB and connected to A2 GND GND for maximum thermal dissipation. Power Output of the Asynchronous Boost Converter for Backlight LEDs. Connect B1 VOUT a 1 F or larger ceramic capacitor from VOUT to ground. Power Input. Connect this pin to the input power supply voltage. Connect a 10 F B2 VIN or larger ceramic capacitor from the VIN to ground. C1 PWM PWM Dimming Input for Backlight LED. Enable Control Input (Active High). The chip is in shutdown mode when the EN C2 EN pin is low. 2 D1 SDA I C Serial Data Input/Output. An external pull-up resistor is required. 2 D2 SCL I C Serial Clock Input. An external pull-up resistor is required. E1 FB2 Single Output 2 for Backlight LED. E2 FB1 Single Output 1 for Backlight LED. Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS4532-00 May 2015 www.richtek.com 2