iw Channel LED Driver for LCD Panel Backlighting 1.0 Features 2.0 Description 3.0 Applications

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1 1.0 Features 6-channel LED driver, 85V (max) per channel Integrated DC-DC boost controller Channel current matching accuracy ±2% Absolute current accuracy ±0.5% Support external power switches for both LED driver and DC-DC boost controller 10V to 28V input power supply Dimming control 14-bit at 120Hz, SPI dimming interface Direct 14-bit at 120Hz, adaptive phase-shifted PWM dimming 8-bit analog dimming PWM-generator clock sources Internal oscillator (Default) Internal PLL clock locked to VSYNC External master input clock Support VSYNC frequency from 50Hz to 480Hz Comprehensive protection features, LED open fault detection (MCU interrupt interface) Single-pin, 2-bit programmable LED short level (3V/6V/12V) fault detection with default at 6V Over-temperature shutdown Boost controller over-current, over-voltage and UVLO protection Package QFP44 with 10mm x 10mm body at 0.8mm pitch Pin-out optimized for a single-layer PCB layout 2.0 Description The iw7011 is a versatile, 6-channel, high precision LED backlight driver for medium to large size LCD display panels. The DC-DC boost controller is integrated on-chip to provide high voltage power supply for the external LED strings. The LED current sink MOSFETs and boost power MOSFET are external and allow maximum flexibility for different current and voltage configurations. Both of the SPI interface control and direct, phase-shifted PWM mode control are supported. Built-in safety features include over-temperature shutdown, boost over-current and over-voltage gate shut down protection, as well as open and short LED detection. 3.0 Applications LED backlighting for LCD-TV sets and LCD monitors C VIN + EN /CSB SCK MOSI MISO /FAULTB VSYNC CLK_IN PWM_IN Analog_dimming VIN VSSA LDO5_A LDO5_D 42 D1 43 G1 41 S1 17 EN iw CSB 39 D2 7 SCK 40 G2 8 MOSI 38 S2 6 MISO 15 FAULTB 36 D3 1 VSYNC 37 G3 5 CLKIN 35 S3 2 PWM_PIN 3 ADIM_PWM 32 D4 33 G4 14 RLS 31 S4 29 D G5 28 CPLL S5 D VDIV G6 S6 25 L D C Vout + 4 PGND RT GNDD GNDA SS 19 GDRV CS VCOMP VFB 6 LED channels Figure 3.1 : iw7011 Simplified Application Diagram Rev. 0.1 iw7011 Page 1

2 4.0 Pinout Description CPLL G1 D1 S1 G2 D2 S2 G3 D3 S3 GNDA VSYNC 1 33 G4 PWM_PIN 2 32 D4 ADIM_PWM 3 31 S4 GNDD 4 30 G5 CLKIN MISO SCK iw D5 S5 G6 MOSI 8 26 D6 CSB 9 25 S6 LDO5_A PGND LDO5_D GDRV VIN VSSA RLS FAULTB DIV EN RT SS VCOMP VFB CS Pin # Name Type Pin Description 1 VSYNC Digital Input VSYNC clock input in SPI dimming mode 2 PWM_PIN Digital Input Direct PWM dimming control input (direct PWM dimming mode) 3 ADIM_PWM Digital Input Analog dimming control input (direct PWM dimming mode) 4 GNDD Ground Digital ground 5 CLKIN Digital Input External clock input pin 6 MISO Digital Output SPI interface data output 7 SCK Digital Input SPI interface clock input (Logic high = 3.3V) 8 MOSI Digital Input SPI interface data input (Logic high = 3.3V) 9 CSB Digital Input SPI interface chip select input, active low. (Logic high = 3.3V) 10 LDO5_A Analog Output LDO compensation pin for internal analog power supply 11 LDO5_D Analog Output LDO compensation pin for internal digital power supply 12 VIN Analog Input Chip power supply input 13 VSSA Ground Quiet analog ground for voltage and current references 14 RLS Analog Input LED short levels selection with using different resistor values 15 FAULTB Digital Output Fault output (active low, open drain) 16 VDIV Analog Input Boost UVLO comparator input to detect a voltage of 1.2V 17 EN Digital Input Chip enable input (Logic high = 3.3V) 18 RT Analog Input Programmable boost switching frequency (ground: 128KHz; ldo5_a: 179KHz) 19 SS Analog Input Programmable soft start time through external capacitor 20 VCOMP Analog Input Boost controller loop compensation 21 VFB Analog Input Boost controller feedback pin (regulated at 1.2V) 22 CS Analog Input Boost current sense input Rev. 0.1 iw7011 Page 2

3 Pin # Name Type Pin Description 23 GDRV Analog Output Boost gate drive for external MOSFET 24 PGND Ground Noisy boost gate pre-driver ground path 25 S6 Analog Input Source of external MOSFET 26 D6 Analog Input Drain of external MOSFET 27 G6 Analog Output Gate of external MOSFET 28 S5 Analog Input Source of external MOSFET 29 D5 Analog Input Drain of external MOSFET 30 G5 Analog Output Gate of external MOSFET 31 S4 Analog Input Source of external MOSFET 32 D4 Analog Input Drain of external MOSFET 33 G4 Analog Output Gate of external MOSFET 34 GNDA Ground 35 S3 Analog Input Source of external MOSFET 36 D3 Analog Input Drain of external MOSFET 37 G3 Analog Output Gate of external MOSFET 38 S2 Analog Input Source of external MOSFET 39 D2 Analog Input Drain of external MOSFET 40 G2 Analog Output Gate of external MOSFET 41 S1 Analog Input Source of external MOSFET 42 D1 Analog Input Drain of external MOSFET 43 G1 Analog Input Gate of external MOSFET 44 CPLL Analog Output PLL external loop filter pin Ground sensing for ILED ground on PCB. Put ILED ground as close as possible to this pin Rev. 0.1 iw7011 Page 3

4 5.0 Absolute Maximum Ratings Absolute maximum ratings are the parameter values or ranges which can cause permanent damage if exceeded. For maximum safe operating conditions, refer to iw7011 datasheet for more information. Symbol Parameter Min Max Unit Notes V IN DC supply voltage at VIN V VIN (Pin 12) only V 5V Maximum voltage for 5V pins V All pins except VIN and D1- D6 V Dx Maximum voltage for pin D1-D V D1, D2, D3, D4, D5, D6 pins I latchup Latch-up immunity ma Norm: EIA/JESD78 T STRG Storage temperature C V ESD T BODY Maximum Junction Temperature Humidity 5 85 % Non Condensing Electrostatic discharge on all 5V pins Body temperature during soldering V 6.0 Recommended Operating Conditions 260 C Norm: MIL 883 E Method 3015 Human body model According to IPC/JEDEC J-STD-020C Symbol Parameter Conditions Min Typ Max Unit θ JA Thermal resistance junction 50 C/W C operate Operating temperature C T j Junction temperature C V IN Supply voltage V Rev. 0.1 iw7011 Page 4

5 7.0 Physical Dimensions This product is RoHS compliant and Halide free. Package is IPC/JEDEC Std 020D Moisture Sensitivity Level Ordering Information Part Number Options Package Description iw tq2e-1 TQFP-44-EP Tape & Reel 1 iw tq2e-2 TQFP-44-EP Tray 2 Note 1: Tape & Reel packing quantity is 1,250/reel. Note 2: Tray minimum packing quantity is 800/carton. Figure 7.1 : Physical dimensions TQFP44 (10mm x 10mm) Rev. 0.1 iw7011 Page 5

6 Trademark Information 2012 iwatt Inc. All rights reserved. iwatt, BroadLED, EZ-EMI, Flickerless, Intelligent AC-DC and LED Power, and PrimAccurate are trademarks of iwatt Inc. All other trademarks and registered trademarks are the property of their respective owners. Contact Information Web: Phone: +1 (408) Fax: +1 (408) iwatt Inc. 675 Campbell Technology Parkway, Suite 150 Campbell, CA Disclaimer and Legal Notices iwatt reserves the right to make changes to its products and to discontinue products without notice. The applications information, schematic diagrams, and other reference information included herein is provided as a design aid only and are therefore provided as-is. iwatt makes no warranties with respect to this information and disclaims any implied warranties of merchantability or non-infringement of third-party intellectual property rights. This product is covered by the following patents: 6,385,059; 6,370,039; 6,862,198; 6,900,995; 6,956,750; 6,990,900; 7,443,700; 7,505,287; 7,589,983; 6,972,969; 7,724,547; 7,876,582; 7,880,447; 7,974,109; 8,018,743; 8,049,481; 7,936,132; 7,433,211; 6,944,034. A full list of iwatt patents can be found at Certain applications using semiconductor products may involve potential risks of death, personal injury, or severe property or environmental damage ( Critical Applications ). iwatt SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED, INTENDED, AUTHORIZED, OR WARRANTED TO BE SUITABLE FOR USE IN LIFE SUPPORT APPLICATIONS, DEVICES OR SYSTEMS, OR OTHER CRITICAL APPLICATIONS. Inclusion of iwatt products in critical applications is understood to be fully at the risk of the customer. Questions concerning potential risk applications should be directed to iwatt Inc. iwatt semiconductors are typically used in power supplies in which high voltages are present during operation. High-voltage safety precautions should be observed in design and operation to minimize the chance of injury. Rev. 0.1 iw7011 Page 6