LP8557, LP85571
SNVSA15B – DECEMBER 2013 – REVISED DECEMBER 2015
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Table of Contents
1 Features .................................................................. 1
2 Applications ........................................................... 1
3 Description ............................................................. 1
4 Revision History..................................................... 2
5 Device Comparison Table..................................... 3
6 Pin Function and Configurations ......................... 3
7 Specifications......................................................... 4
7.1 Absolute Maximum Ratings ...................................... 4
7.2 ESD Ratings.............................................................. 4
7.3 Recommended Operating Conditions....................... 4
7.4 Thermal Information .................................................. 4
7.5 Electrical Characteristics........................................... 5
7.6 Boost Converter Electrical Characteristics................ 5
7.7 LED Driver Electrical Characteristics (LED1 To LED6
Pins) ........................................................................... 5
7.8 PWM Interface Characteristics (PWM Pin) ............... 6
7.9 Logic Interface Characteristics
(PWM, FSET/SDA, ISET/SCL Pins) .......................... 6
7.10 I2C Serial Bus Timing Parameters (SDA, SCL) ..... 7
7.11 Typical Characteristics ............................................ 8
8 Detailed Description ............................................ 11
8.1 Overview ................................................................. 11
8.2 Functional Block Diagram ....................................... 11
8.3 Feature Description................................................. 12
8.4 Device Functional Modes........................................ 20
8.5 Programming........................................................... 20
8.6 Register Maps ......................................................... 24
9 Application and Implementation ........................ 31
9.1 Application Information............................................ 31
9.2 Typical Applications ............................................... 34
10 Power Supply Recommendations ..................... 38
11 Layout................................................................... 38
11.1 Layout Guidelines ................................................. 38
11.2 Layout Example .................................................... 42
12 Device and Documentation Support ................. 43
12.1 Device Support .................................................... 43
12.2 Related Links ........................................................ 43
12.3 Community Resources.......................................... 43
12.4 Trademarks ........................................................... 43
12.5 Electrostatic Discharge Caution ............................ 43
12.6 Glossary ................................................................ 43
13 Mechanical, Packaging, and Orderable
Information ........................................................... 43
4 Revision History
Changes from Revision A (June 2014) to Revision B
Page
• moved storage temperature range to Abs Max table ............................................................................................................ 4
• Changed Handling Ratings table to ESD Ratings table ........................................................................................................ 4
• Updated Thermal Information table ....................................................................................................................................... 4
• Changed word "safety" to "fault detection" ........................................................................................................................... 11
• Deleted "to 25% of the brightness range" ........................................................................................................................... 16
• Changed PGEN register table and descriptions .................................................................................................................. 28
• Changed fixed typo "2.4.4 kHz" to "24.4 kHz" ..................................................................................................................... 28
• Added note to beginning of Application and Implementation section .................................................................................. 31
• Added Community Resources section ................................................................................................................................ 43
Changes from Original (December 2013) to Revision A
Page
• Changed formatting to match new TI datasheet guidelines; added Device Information and Handling Ratings table,
Layout, and Device and Documentation Support sections; reformatted Detailed Description and Application and
Implementation sections, fix typographical errors. ................................................................................................................ 1
• Changed 6 LED strings to 5 LED Strings to correct typo....................................................................................................... 8
• Added PWM Input Duty Measurement subsection............................................................................................................... 13
• Changed description for "0" BFSET as well as description of register table for BFSET bit ................................................ 29
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