SNVSA52E
August 2014 – September 2016
LM3644
PRODUCTION DATA.
1
Features
2
Applications
3
Description
4
Revision History
5
Device Comparison Table
6
Pin Configuration and Functions
7
Specifications
7.1
Absolute Maximum Ratings
7.2
ESD Ratings
7.3
Recommended Operating Conditions
7.4
Thermal Information
7.5
Electrical Characteristics
7.6
Timing Requirements
7.7
Switching Characteristics
7.8
Typical Characteristics
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Flash Mode
8.3.2
Torch Mode
8.3.3
IR Mode
8.4
Device Functioning Modes
8.4.1
Start-Up (Enabling The Device)
8.4.2
Pass Mode
8.4.3
Power Amplifier Synchronization (TX)
8.4.4
Input Voltage Flash Monitor (IVFM)
8.4.5
Fault/Protections
8.4.5.1
Fault Operation
8.4.5.2
Flash Time-Out
8.4.5.3
Overvoltage Protection (OVP)
8.4.5.4
Current Limit
8.4.5.5
NTC Thermistor Input (Torch/Temp)
8.4.5.6
Undervoltage Lockout (UVLO)
8.4.5.7
Thermal Shutdown (TSD)
8.4.5.8
LED and/or VOUT Short Fault
8.5
Programming
8.5.1
Control Truth Table
8.5.2
I2C-Compatible Interface
8.5.2.1
Data Validity
8.5.2.2
Start and Stop Conditions
8.5.2.3
Transferring Data
8.5.2.4
I2C-Compatible Chip Address
8.6
Register Descriptions
8.6.1
Enable Register (0x01)
8.6.2
IVFM Register (0x02)
8.6.3
LED1 Flash Brightness Register (0x03)
8.6.4
LED2 Flash Brightness Register (0x04)
8.6.5
LED1 Torch Brightness Register (0x05)
8.6.6
LED2 Torch Brightness Register (0x06)
8.6.7
Boost Configuration Register (0x07)
8.6.8
Timing Configuration Register (0x08)
8.6.9
TEMP Register (0x09)
8.6.10
Flags1 Register (0x0A)
8.6.11
Flags2 Register (0x0B)
8.6.12
Device ID Register (0x0C)
8.6.13
Last Flash Register (0x0D)
9
Applications and Implementation
9.1
Application Information
9.2
Typical Application
9.2.1
Design Requirements
9.2.2
Detailed Design Procedure
9.2.2.1
Output Capacitor Selection
9.2.2.2
Input Capacitor Selection
9.2.2.3
Inductor Selection
9.2.3
Application Curves
10
Power Supply Recommendations
11
Layout
11.1
Layout Guidelines
11.2
Layout Example
12
Device and Documentation Support
12.1
Device Support
12.1.1
Third-Party Products Disclaimer
12.2
Related Documentation
12.2.1
Related Links
12.2.2
Receiving Notification of Documentation Updates
12.2.3
Community Resources
12.3
Trademarks
12.4
Electrostatic Discharge Caution
12.5
Glossary
13
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
YFF|12
MXBG343
Thermal pad, mechanical data (Package|Pins)
Orderable Information
snvsa52e_oa
snvsa52e_pm
5 Device Comparison Table
ORDERING PART NUMBER
MAXIMUM TORCH CURRENT PER CHANNEL
FLASH TIME-OUT RANGE
LM3644YFFR
179 mA
10 ms to 400 ms
LM3644TTYFFR
360 mA
40 ms to 1600 ms