SLVSJ80
October 2025
LM25139
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Pin Configuration and Functions
5
Specifications
5.1
Absolute Maximum Ratings
5.2
ESD Ratings
5.3
Recommended Operating Conditions
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
Input Voltage Range (VIN )
6.3.2
High-Voltage Bias Supply Regulator (VCC)
6.3.3
Precision Enable (EN)
6.3.4
Power-Good Monitor (PG)
6.3.5
Switching Frequency (RT)
6.3.6
Dual Random Spread Spectrum (DRSS)
6.3.7
Soft Start
6.3.8
Output Voltage Setpoint (FB)
6.3.9
Minimum Controllable On Time
6.3.10
Error Amplifier and PWM Comparator (FB)
6.3.11
Slope Compensation
6.3.12
Inductor Current Sense (ISNS, VOUT)
6.3.12.1
Shunt Current Sensing
6.3.12.2
Inductor DCR Current Sensing
6.3.12.3
Hiccup-Mode Current Limiting
6.4
Device Functional Modes
6.4.1
Sleep Mode
6.4.2
Forced PWM and Synchronization (FPWM/SYNC)
6.4.3
Thermal Shutdown
7
Application and Implementation
7.1
Application Information
7.1.1
Power Train Components
7.1.1.1
Buck Inductor
7.1.1.2
Output Capacitors
7.1.1.3
Input Capacitors
7.1.1.4
Power MOSFETs
7.1.1.5
EMI Filter
7.1.2
Error Amplifier and Compensation
7.2
Typical Applications
7.2.1
Design 1 – High Efficiency 1MHz Synchronous Buck Regulator
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
Buck Inductor
7.2.1.2.3
Current-Sense Components
7.2.1.2.4
Output Capacitors
7.2.1.2.5
Input Capacitors
7.2.1.2.6
Feedback Resistors
7.2.1.2.7
Frequency Set Resistor
7.2.1.2.8
Compensation Components
7.2.1.3
Application Curves
7.2.2
Design 2 – High-Efficiency, 440kHz, Synchronous Buck Regulator
7.2.2.1
Design Requirements
7.2.2.2
Detailed Design Procedure
7.2.2.3
Application Curves
7.3
Power Supply Recommendations
7.4
Layout
7.4.1
Layout Guidelines
7.4.1.1
Power Stage Layout
7.4.1.2
Gate Drive Layout
7.4.1.3
PWM Controller Layout
7.4.1.4
Thermal Design and Layout
7.4.1.5
Ground Plane Design
7.4.2
Layout Example
8
Device and Documentation Support
8.1
Device Support
8.1.1
Development Support
8.1.1.1
Custom Design With WEBENCH® Tools
8.2
Documentation Support
8.2.1
Related Documentation
8.2.1.1
Low-EMI Design Resources
8.2.1.2
Thermal Design Resources
8.2.1.3
PCB Layout Resources
8.3
Receiving Notification of Documentation Updates
8.4
Support Resources
8.5
Trademarks
8.6
Electrostatic Discharge Caution
8.7
Glossary
9
Revision History
10
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
RGT|16
MPQF119H
Thermal pad, mechanical data (Package|Pins)
RGT|16
QFND098T
Orderable Information
slvsj80_oa
slvsj80_pm
Data Sheet
LM25139
42V, Synchronous Buck DC/DC Controller With Dual Random Spread Spectrum for Advanced EMI Mitigation