STEVAL-ISA056V1 6 rows - 30 mA LEDs driver with boost converter for LCD panels backlight evaluation board based on the PM6600 Data Brief Features ■ ■ Boost section – 4.5 V to 28 V input voltage range – Internal Power MOSFET – Internal +5 V LDO for device supply – Up to 36 V output voltage – Constant frequency peak current-mode ctrl – 200 kHz to 1 MHz adjustable switching frequency – External sync for multi-device application – Pulse-skip power saving mode at light load – Programmable soft-start – Programmable OVP protection – Single ceramic output capacitor – Latched thermal shutdown STEVAL-ISA056V1 managed). The device allows to detect and manage the open and shorted LED faults and to let unused rows floating. Basic protections (output over-voltage, internal MOSFET overcurrent and thermal shutdown) are provided. Backlight driver section – Six rows with 30mA maximum current capability (adjustable) – Up to 10 W LEDs per row – Rows disable option – Less than 500 ns minimum dimming time (1% minimum dimming duty-cycle at 20 kHz dimming frequency) – ±2.0% current matching between rows – LED failure (open and short circuit) detection Description This evaluation board based on the PM6600 consists of a high efficiency monolithic boost converter and six controlled current generators (rows) specifically designed to supply LEDs arrays used in the backlight of LCD panels. The device can manage an output voltage up to 36 V (i.e. ten white-LEDs per row). The generators can be externally programmed to sink up to 30 mA and can be dimmed via a PWM signal (1% dimming duty-cycle at 20 kHz can be March 2008 Rev 1 For further information contact your local STMicroelectronics sales office. 1/4 www.st.com 4 VIN IN- DIM DI EN SY NC R12 NM R13 NM 100k R10 D3 NM C12 NM 4n7 C11 RES SW3 FAULT AVCC AV RED, D, 3mA D2 MODE SW2 R11 1k2 2 4n7 N. N.M. R3 2k4 C8 R9 100k 10 1 AVCC C9 LED_EN J2 3n3 C7 R5 330k 33 AVCC AV 1u C6 10 100n C5 AVCC AV FSW SS COMP AVCC AV 7 6 SW1 FSW TP13 24 1 5 20 21 22 R4 4R7 SS COMP MODE DIM DI EN FAULT LDO5 AVCC U1 23 R6 51k VIN PM660 6600 RILIM RI SYNC SY C1 10u RILIM RI 2 FSW 4 8 VIN 3 L1 19 R7 180k BILIM 6u8 THPD ROW6 ROW5 ROW4 ROW3 ROW2 ROW1 PGND PG SLOPE OVSEL OVSE LX 2/4 BILIM 25 16 15 14 13 12 11 17 9 18 OVSEL OVSE STPS PS1L40M D1 R2 16k R1 510k C10 60p 560 SLOPE SLOP C13 22p ROW1 R8 80k 680 ROW2 ROW3 C2 2u2 ROW4 C3 2u2 ROW5 TP8 GND C4 N.M. N. ROW6 J8 VBOOST VBOOS HEA EADER R8 8 7 6 5 4 3 2 1 TP7 Figure 1. SGND SG 1 10 VIN IN+ Circuit schematic STEVAL-ISA056V1 Circuit schematic Schematic STEVAL-ISA056V1 2 Revision history Revision history Table 1. Document revision history Date Revision 10-Mar-2008 1 Changes Initial release. 3/4 STEVAL-ISA056V1 Please Read Carefully: Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. Purchasers are solely responsible for the choice, selection and use of the ST products and services described herein, and ST assumes no liability whatsoever relating to the choice, selection or use of the ST products and services described herein. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. If any part of this document refers to any third party products or services it shall not be deemed a license grant by ST for the use of such third party products or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoever of such third party products or services or any intellectual property contained therein. UNLESS OTHERWISE SET FORTH IN ST’S TERMS AND CONDITIONS OF SALE ST DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY WITH RESPECT TO THE USE AND/OR SALE OF ST PRODUCTS INCLUDING WITHOUT LIMITATION IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION), OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT. UNLESS EXPRESSLY APPROVED IN WRITING BY AN AUTHORIZED ST REPRESENTATIVE, ST PRODUCTS ARE NOT RECOMMENDED, AUTHORIZED OR WARRANTED FOR USE IN MILITARY, AIR CRAFT, SPACE, LIFE SAVING, OR LIFE SUSTAINING APPLICATIONS, NOR IN PRODUCTS OR SYSTEMS WHERE FAILURE OR MALFUNCTION MAY RESULT IN PERSONAL INJURY, DEATH, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE. ST PRODUCTS WHICH ARE NOT SPECIFIED AS "AUTOMOTIVE GRADE" MAY ONLY BE USED IN AUTOMOTIVE APPLICATIONS AT USER’S OWN RISK. Resale of ST products with provisions different from the statements and/or technical features set forth in this document shall immediately void any warranty granted by ST for the ST product or service described herein and shall not create or extend in any manner whatsoever, any liability of ST. ST and the ST logo are trademarks or registered trademarks of ST in various countries. Information in this document supersedes and replaces all information previously supplied. The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners. © 2008 STMicroelectronics - All rights reserved STMicroelectronics group of companies Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America www.st.com 4/4