SNVS603D
August 2009 – July 2019
LM3424
PRODUCTION DATA.
1
Features
2
Applications
Typical Boost Application Circuit
3
Description
4
Revision History
5
Pin Configuration and Functions
Pin Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Information
6.5
Electrical Characteristics
6.6
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
Current Regulators
7.3.2
Peak Current Mode Control
7.3.3
Average LED Current
7.3.4
Thermal Foldback and Analog Dimming
7.3.5
Current Sense and Current Limit
7.3.6
Slope Compensation
7.3.7
Control Loop Compensation
7.3.8
Start-Up Regulator and Soft-Start
7.3.9
Overvoltage Lockout (OVLO)
7.3.10
Input Undervoltage Lockout (UVLO)
7.3.10.1
UVLO Only
7.3.10.2
PWM Dimming and UVLO
7.3.11
PWM Dimming
7.3.12
Thermal Shutdown
7.4
Device Functional Modes
8
Application and Implementation
8.1
Application Information
8.1.1
Inductor
8.1.2
LED Dynamic Resistance
8.1.3
Output Capacitor
8.1.4
Input Capacitors
8.1.5
Main MOSFET and Dimming MOSFET
8.1.6
Re-Circulating Diode
8.1.7
Switching Frequency
8.2
Typical Applications
8.2.1
Basic Topology Schematics
8.2.1.1
Design Requirements
8.2.1.2
Detailed Design Procedure
8.2.1.2.1
Operating Point
8.2.1.2.2
Switching Frequency
8.2.1.2.3
Average LED Current
8.2.1.2.4
Thermal Foldback
8.2.1.2.5
Inductor Ripple Current
8.2.1.2.6
LED Ripple Current
8.2.1.2.7
Peak Current Limit
8.2.1.2.8
Slope Compensation
8.2.1.2.9
Loop Compensation
8.2.1.2.10
Input Capacitance
8.2.1.2.11
NFET
8.2.1.2.12
Diode
8.2.1.2.13
Output OVLO
8.2.1.2.14
Input UVLO
8.2.1.2.15
Soft-Start
8.2.1.2.16
PWM Dimming Method
8.2.1.2.17
Analog Dimming Method
8.2.2
Buck-Boost Application
8.2.2.1
Design Requirements
8.2.2.2
Detailed Design Procedure
8.2.2.2.1
Operating Point
8.2.2.2.2
Switching Frequency
8.2.2.2.3
Average LED Current
8.2.2.2.4
Thermal Foldback
8.2.2.2.5
Inductor Ripple Current
8.2.2.2.6
Output Capacitance
8.2.2.2.7
Peak Current Limit
8.2.2.2.8
Slope Compensation
8.2.2.2.9
Loop Compensation
8.2.2.2.10
Input Capacitance
8.2.2.2.11
NFET
8.2.2.2.12
Diode
8.2.2.2.13
Input UVLO
8.2.2.2.14
Output OVLO
8.2.2.2.15
Soft-Start
8.2.2.3
Application Curve
8.2.3
Boost Application
8.2.3.1
Design Requirements
8.2.3.2
Detailed Design Procedure
8.2.4
Buck-Boost Application
8.2.4.1
Design Requirements
8.2.4.2
Detailed Design Procedures
8.2.5
Boost Application
8.2.5.1
Design Requirements
8.2.5.2
Detailed Design Procedure
8.2.6
Buck-Boost Application
8.2.6.1
Design Requirements
8.2.6.2
Detailed Design Procedure
8.2.7
Buck Application
8.2.7.1
Design Requirements
8.2.7.2
Detailed Design Procedure
8.2.8
Buck-Boost Application
8.2.8.1
Design Requirements
8.2.8.2
Detailed Design Procedure
8.2.9
SEPIC Application
8.2.9.1
Design Requirements
8.2.9.2
Detailed Design Procedure
9
Power Supply Recommendations
9.1
Input Supply Current Limit
10
Layout
10.1
Layout Guidelines
10.2
Layout Example
11
Device and Documentation Support
11.1
Device Support
11.1.1
Third-Party Products Disclaimer
11.2
Community Resources
11.3
Trademarks
11.4
Electrostatic Discharge Caution
11.5
Glossary
12
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
PWP|20
MHTS001G
Thermal pad, mechanical data (Package|Pins)
PWP|20
PPTD289
Orderable Information
snvs603d_oa
snvs603d_pm
8.2.3
Boost Application
Figure 41.
Boost Application