SNVS967A
August 2014 – November 2014
LM3643
PRODUCTION DATA.
1
Features
2
Applications
3
Description
4
Simplified Schematic
5
Revision History
6
Device Comparison Table
7
Pin Configuration and Functions
8
Specifications
8.1
Absolute Maximum Ratings
8.2
Handling Ratings
8.3
Recommended Operating Conditions
8.4
Thermal Information
8.5
Electrical Characteristics
8.6
Timing Requirements
8.7
Switching Characteristics
8.8
Typical Characteristics
9
Detailed Description
9.1
Overview
9.2
Functional Block Diagram
9.3
Feature Description
9.3.1
Flash Mode
9.3.2
Torch Mode
9.3.3
IR Mode
9.4
Device Functioning Modes
9.4.1
Start-Up (Enabling The Device)
9.4.2
Pass Mode
9.4.3
Power Amplifier Synchronization (TX)
9.4.4
Input Voltage Flash Monitor (IVFM)
9.4.5
Fault/Protections
9.4.5.1
Fault Operation
9.4.5.2
Flash Time-Out
9.4.5.3
Overvoltage Protection (OVP)
9.4.5.4
Current Limit
9.4.5.5
NTC Thermistor Input (Torch/Temp)
9.4.5.6
Undervoltage Lockout (UVLO)
9.4.5.7
Thermal Shutdown (TSD)
9.4.5.8
LED and/or VOUT Short Fault
9.5
Programming
9.5.1
Control Truth Table
9.5.2
I2C-Compatible Interface
9.5.2.1
Data Validity
9.5.2.2
Start and Stop Conditions
9.5.2.3
Transferring Data
9.5.2.4
I2C-Compatible Chip Address
9.6
Register Descriptions
9.6.1
Enable Register (0x01)
9.6.2
IVFM Register (0x02)
9.6.3
LED1 Flash Brightness Register (0x03)
9.6.4
LED2 Flash Brightness Register (0x04)
9.6.5
LED1 Torch Brightness Register (0x05)
9.6.6
LED2 Torch Brightness Register (0x06)
9.6.7
Boost Configuration Register (0x07)
9.6.8
Timing Configuration Register (0x08)
9.6.9
TEMP Register (0x09)
9.6.10
Flags1 Register (0x0A)
9.6.11
Flags2 Register (0x0B)
9.6.12
Device ID Register (0x0C)
9.6.13
Last Flash Register (0x0D)
10
Applications and Implementation
10.1
Application Information
10.2
Typical Application
10.2.1
Design Requirements
10.2.2
Detailed Design Procedure
10.2.2.1
Output Capacitor Selection
10.2.2.2
Input Capacitor Selection
10.2.2.3
Inductor Selection
10.2.3
Application Curves
11
Power Supply Recommendations
12
Layout
12.1
Layout Guidelines
12.2
Layout Example
13
Device and Documentation Support
13.1
Device Support
13.1.1
Third-Party Products Disclaimer
13.2
Related Documentation
13.2.1
Related Links
13.3
Trademarks
13.4
Electrostatic Discharge Caution
13.5
Glossary
14
Mechanical, Packaging, and Orderable Information
6 Device Comparison Table
ORDERING PART NUMBER
I
2
C ADDRESS
LM3643YFFR
0x63
LM3643AYFFR
0x67