SNVSC00A
February 2023 – January 2025
LM5148-Q1
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Description (continued)
5
Pin Configuration and Functions
5.1
Wettable Flanks
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Information
6.5
Thermal Information
6.6
Electrical Characteristics
6.7
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
Input Voltage Range (VIN)
7.3.2
High-Voltage Bias Supply Regulator (VCC, VCCX, VDDA)
7.3.3
Precision Enable (EN)
7.3.4
Power-Good Monitor (PG)
7.3.5
Switching Frequency (RT)
7.3.6
Dual Random Spread Spectrum (DRSS)
7.3.7
Soft Start
7.3.8
Output Voltage Setpoint (FB)
7.3.9
Minimum Controllable On Time
7.3.10
Error Amplifier and PWM Comparator (FB, EXTCOMP)
7.3.11
Slope Compensation
7.3.12
Inductor Current Sense (ISNS+, VOUT)
7.3.12.1
Shunt Current Sensing
7.3.12.2
Inductor DCR Current Sensing
7.3.13
Hiccup Mode Current Limiting
7.3.14
High-Side and Low-Side Gate Drivers (HO, LO)
7.3.15
Output Configurations (CNFG)
7.3.16
Single-Output Dual-Phase Operation
7.4
Device Functional Modes
7.4.1
Sleep Mode
7.4.2
Pulse Frequency Modulation and Synchronization (PFM/SYNC)
7.4.3
Thermal Shutdown
8
Application and Implementation
8.1
Application Information
8.1.1
Power Train Components
8.1.1.1
Buck Inductor
8.1.1.2
Output Capacitors
8.1.1.3
Input Capacitors
8.1.1.4
Power MOSFETs
8.1.1.5
EMI Filter
8.1.2
Error Amplifier and Compensation
8.2
Typical Applications
8.2.1
Design 1 – High Efficiency 2.1MHz Synchronous Buck Regulator
8.2.1.1
Design Requirements
8.2.1.2
Detailed Design Procedure
8.2.1.2.1
Custom Design with WEBENCH® Tools
8.2.1.2.2
Custom Design with Excel Quickstart Tool
8.2.1.2.3
Buck Inductor
8.2.1.2.4
Current-Sense Resistance
8.2.1.2.5
Output Capacitors
8.2.1.2.6
Input Capacitors
8.2.1.2.7
Frequency Set Resistor
8.2.1.2.8
Feedback Resistors
8.2.1.2.9
Compensation Components
8.2.1.3
Application Curves
8.2.2
Design 2 – High Efficiency 48-V to 12-V 400-kHz Synchronous Buck Regulator
8.2.2.1
Design Requirements
8.2.2.2
Detailed Design Procedure
8.2.2.3
Application Curves
8.2.3
Design 3 – High Efficiency 440-kHz Synchronous Buck Regulator
8.2.3.1
Design Requirements
8.2.3.2
Detailed Design Procedure
8.2.3.3
Application Curves
8.2.4
Design 4 – Dual-Phase 400-kHz 20-A Synchronous Buck Regulator
8.2.4.1
Design Requirements
8.2.4.2
Detailed Design Procedure
8.2.4.3
Application Curves
8.3
Power Supply Recommendations
8.4
Layout
8.4.1
Layout Guidelines
8.4.1.1
Power Stage Layout
8.4.1.2
Gate-Drive Layout
8.4.1.3
PWM Controller Layout
8.4.1.4
Thermal Design and Layout
8.4.1.5
Ground Plane Design
8.4.2
Layout Example
9
Device and Documentation Support
9.1
Device Support
9.1.1
Development Support
9.1.1.1
Custom Design with WEBENCH® Tools
9.2
Documentation Support
9.2.1
Related Documentation
9.2.1.1
PCB Layout Resources
9.2.1.2
Thermal Design Resources
9.3
Receiving Notification of Documentation Updates
9.4
Support Resources
9.5
Trademarks
9.6
Electrostatic Discharge Caution
9.7
Glossary
10
Revision History
11
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
RGY|19
MPQF777A
RGY|24
MPQF143E
Thermal pad, mechanical data (Package|Pins)
RGY|19
QFND668
RGY|24
QFND819
Orderable Information
snvsc00a_oa
snvsc00a_pm
Data Sheet
LM5148-Q1
80V,
Automotive,
Synchronous, Buck DC/DC Controller With Ultra-Low I
Q
and Dual Random Spread Spectrum