SNVSAT9
June 2017
LM25145
PRODUCTION DATA.
1
Features
2
Applications
3
Description
4
Revision History
5
Description (continued)
6
Pin Configuration and Functions
6.1
Wettable Flanks
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
Switching Characteristics
7.7
Typical Characteristics
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Input Range (VIN)
8.3.2
Output Voltage Setpoint and Accuracy (FB)
8.3.3
High-Voltage Bias Supply Regulator (VCC)
8.3.4
Precision Enable (EN/UVLO)
8.3.5
Power Good Monitor (PGOOD)
8.3.6
Switching Frequency (RT, SYNCIN)
8.3.6.1
Frequency Adjust
8.3.6.2
Clock Synchronization
8.3.7
Configurable Soft-Start (SS/TRK)
8.3.7.1
Tracking
8.3.8
Voltage-Mode Control (COMP)
8.3.9
Gate Drivers (LO, HO)
8.3.10
Current Sensing and Overcurrent Protection (ILIM)
8.3.11
OCP Duty Cycle Limiter
8.4
Device Functional Modes
8.4.1
Shutdown Mode
8.4.2
Standby Mode
8.4.3
Active Mode
8.4.4
Diode Emulation Mode
8.4.5
Thermal Shutdown
9
Application and Implementation
9.1
Application Information
9.1.1
Design and Implementation
9.1.2
Power Train Components
9.1.2.1
Inductor
9.1.2.2
Output Capacitors
9.1.2.3
Input Capacitors
9.1.2.4
Power MOSFETs
9.1.3
Control Loop Compensation
9.1.4
EMI Filter Design
9.2
Typical Applications
9.2.1
Design 1 - 20-A High-Efficiency Synchronous Buck Regulator for Telecom Power Applications
9.2.1.1
Design Requirements
9.2.1.2
Detailed Design Procedure
9.2.1.3
Custom Design With WEBENCH® Tools
9.2.1.4
Application Curves
9.2.2
Design 2 - High Density, 12-V, 8-A Rail With LDO Low-Noise Auxiliary Output for Industrial Applications
9.2.2.1
Design Requirements
9.2.2.2
Detailed Design Procedure
9.2.2.2.1
Application Curves
9.2.3
Design 3 - Powering a Multicore DSP From a 24-V Rail
9.2.3.1
Design Requirements
9.2.3.2
Detailed Design Procedure
9.2.3.3
Application Curves
10
Power Supply Recommendations
11
Layout
11.1
Layout Guidelines
11.1.1
Power Stage Layout
11.1.2
Gate Drive Layout
11.1.3
PWM Controller Layout
11.1.4
Thermal Design and Layout
11.1.5
Ground Plane Design
11.2
Layout Example
12
Device and Documentation Support
12.1
Device Support
12.1.1
Third-Party Products Disclaimer
12.1.2
Development Support
12.1.3
Custom Design With WEBENCH® Tools
12.2
Documentation Support
12.2.1
Related Documentation
12.2.1.1
PCB Layout Resources
12.2.1.2
Thermal Design Resources
12.3
Related Links
12.4
Receiving Notification of Documentation Updates
12.5
Community Resources
12.6
Trademarks
12.7
Electrostatic Discharge Caution
12.8
Glossary
13
Mechanical, Packaging, and Orderable Information
4
Revision History
DATE
REVISION
NOTES
June 2017
*
Initial release
SPACER