SLUSEP7
December 2022
LMR51440
,
LMR51450
PRODUCTION DATA
1
Features
2
Applications
3
Description
4
Revision History
5
Device Comparison Table
6
Pin Configuration and Functions
7
Specifications
7.1
Absolute Maximum Ratings
ESD Ratings
7.2
Recommended Operating Conditions
7.3
Thermal Information
7.4
Electrical Characteristics
7.5
System Characteristics
7.6
Typical Characteristics
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Fixed Frequency Peak Current Mode Control
8.3.2
Adjustable Output Voltage
8.3.3
Enable
8.3.4
Switching Frequency
8.3.5
Power-Good Flag Output
8.3.6
Minimum ON-Time, Minimum OFF-Time, and Frequency Foldback
8.3.7
Bootstrap Voltage
8.3.8
Overcurrent and Short-Circuit Protection
8.3.9
Soft Start
8.3.10
Thermal Shutdown
8.4
Device Functional Modes
8.4.1
Shutdown Mode
8.4.2
Active Mode
8.4.3
CCM Mode
8.4.4
Light-Load Operation (PFM Version)
8.4.5
Light-Load Operation (FPWM Version)
9
Application and Implementation
9.1
Application Information
9.2
Typical Application
9.2.1
Design Requirements
9.2.2
Detailed Design Procedure
9.2.2.1
Output Voltage Set-Point
9.2.2.2
Switching Frequency
9.2.2.3
Inductor Selection
9.2.2.4
Output Capacitor Selection
9.2.2.5
Input Capacitor Selection
9.2.2.6
Bootstrap Capacitor
9.2.2.7
Undervoltage Lockout Set-Point
9.2.3
Application Curves
9.3
Best Design Practices
9.4
Power Supply Recommendations
9.5
Layout
9.5.1
Layout Guidelines
9.5.1.1
Compact Layout for EMI Reduction
9.5.1.2
Feedback Resistors
9.5.2
Layout Example
10
Device and Documentation Support
10.1
Device Support
10.1.1
Development Support
10.1.1.1
Custom Design With WEBENCH® Tools
10.2
Documentation Support
10.2.1
Related Documentation
10.3
Receiving Notification of Documentation Updates
10.4
Support Resources
10.5
Trademarks
10.6
Electrostatic Discharge Caution
10.7
Glossary
11
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
DRR|12
MPSS085A
Thermal pad, mechanical data (Package|Pins)
DRR|12
PPTD377
Orderable Information
slusep7_oa
slusep7_pm
1
Features
Functional Safety-Capable
Documentation available to aid functional safety system design
Configured for rugged industrial applications
Wide Input voltage range: 4 V to 36 V
4-A or 5-A continuous output current
±1.0% tolerance voltage reference at room temperature
Minimum switching-on time: 75 ns (typical)
Low Quiescent current: 25 µA
Adjustable Frequency: 200 kHz to 1.1 MHz
Frequency spread spectrum (PFM variant)
Protection features
Precision enable input
Open-drain PGOOD
V
IN
undervoltage lockout (UVLO)
Cycle-by-cycle current limiting
Short-circuit protection with hiccup mode
Thermal shutdown
Low dropout mode operation
Junction temperature range: –40°C to 150°C
Small solution size and ease of use
Integrated synchronous rectification
Internal compensation for ease of use
WSON-12 package
Various options in pin-to-pin compatible package
PFM and forced PWM (FPWM) options
Create a custom design using the
LMR5144x0
with the
WEBENCH
®
Power Designer