SNVS346H
November 2007 – October 2024
LM3481
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Pin Configuration and Functions
Pin Functions
5
Specifications
5.1
Absolute Maximum Ratings
5.2
ESD Ratings: LM3481
5.3
Recommended Operating Ratings
5.4
Thermal Information
5.5
Electrical Characteristics
5.6
Typical Characteristics
6
Detailed Description
6.1
Overview
6.2
Functional Block Diagram
6.3
Feature Description
6.3.1
Overvoltage Protection
6.3.2
Bias Voltage
6.3.3
Slope Compensation Ramp
6.3.4
Frequency Adjust, Synchronization, and Shutdown
6.3.5
Undervoltage Lockout (UVLO) Pin
6.3.6
Short-Circuit Protection
6.4
Device Functional Modes
7
Application and Implementation
7.1
Application Information
7.2
Typical Applications
7.2.1
Boost Converter
7.2.1.1
Design Requirements
7.2.1.2
Detailed Design Procedure
7.2.1.2.1
Custom Design with WEBENCH Tools
7.2.1.2.2
Power Inductor Selection
7.2.1.2.3
Programming the Output Voltage and Output Current
7.2.1.2.4
Current Limit With Additional Slope Compensation
7.2.1.2.5
Power Diode Selection
7.2.1.2.6
Power MOSFET Selection
7.2.1.2.7
Input Capacitor Selection
7.2.1.2.8
Output Capacitor Selection
7.2.1.2.9
Driver Supply Capacitor Selection
7.2.1.2.10
Compensation
7.2.1.3
Application Curve
7.2.2
Typical SEPIC Converter
7.2.2.1
Design Requirements
7.2.2.2
Detailed Design Procedure
7.2.2.2.1
Power MOSFET Selection
7.2.2.2.2
Power Diode Selection
7.2.2.2.3
Selection of Inductors L1 and L2
7.2.2.2.4
Sense Resistor Selection
7.2.2.2.5
SEPIC Capacitor Selection
7.2.2.2.6
Input Capacitor Selection
7.2.2.2.7
Output Capacitor Selection
7.2.2.3
Application Curve
7.3
Power Supply Recommendations
7.4
Layout
7.4.1
Layout Guidelines
7.4.2
Layout Example
8
Device and Documentation Support
8.1
Documentation Support
8.1.1
Custom Design with WEBENCH Tools
8.1.2
Related Documentation
8.2
Receiving Notification of Documentation Updates
8.3
Support Resources
8.4
Trademarks
9
Revision History
10
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
DGS|10
MPDS035C
Thermal pad, mechanical data (Package|Pins)
Orderable Information
snvs346h_oa
snvs346h_pm
Data Sheet
LM3481
High-Efficiency Controller for Boost, SEPIC and Flyback DC/DC Converters