SLUSFM3
September 2024
LMR51425-Q1
,
LMR51435-Q1
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Device Comparison Table
5
Pin Configuration and 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
System Characteristics
6.7
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
Fixed Frequency Peak Current Mode Control
7.3.2
Adjustable Output Voltage
7.3.3
Enable
7.3.4
Switching Frequency
7.3.5
Power-Good Flag Output
7.3.6
Minimum ON-Time, Minimum OFF-Time, and Frequency Foldback
7.3.7
Bootstrap Voltage
7.3.8
Overcurrent and Short-Circuit Protection
7.3.9
Soft Start
7.3.10
Thermal Shutdown
7.4
Device Functional Modes
7.4.1
Shutdown Mode
7.4.2
Active Mode
7.4.3
CCM Mode
7.4.4
Light-Load Operation (PFM Version)
7.4.5
Light-Load Operation (FPWM Version)
8
Application and Implementation
8.1
Application Information
8.2
Typical Application
8.2.1
Design Requirements
8.2.2
Detailed Design Procedure
8.2.2.1
Custom Design With WEBENCH® Tools
8.2.2.2
Output Voltage Set-Point
8.2.2.3
Switching Frequency
8.2.2.4
Inductor Selection
8.2.2.5
Output Capacitor Selection
8.2.2.6
Input Capacitor Selection
8.2.2.7
Bootstrap Capacitor
8.2.2.8
Undervoltage Lockout Setpoint
8.2.3
Application Curves
8.3
Power Supply Recommendations
8.4
Layout
8.4.1
Layout Guidelines
8.4.1.1
Compact Layout for EMI Reduction
8.4.1.2
Feedback Resistors
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
9.3
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
11.1
Tape and Reel Information
1
Features
AEC-Q100 qualified for automotive applications
Device temperature grade 1: –40°C to +125°C ambient operating temperature
Functional Safety-Capable
Documentation available to aid functional safety system design
Supports automotive system requirements
:
Wide input voltage range: 4V to 36V
Continuous output current:
2.5A
or
3.5A
±1.0% tolerance voltage reference at room temperature
Minimum switching-on time: 75ns (typical)
Low quiescent current: 25µA
Adjustable frequency: 200kHz to
1MHz
Frequency spread spectrum
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
Small design size and ease of use
Integrated synchronous rectification
Internal compensation for ease of use
WSON-12 package
PFM and FPWM options in pin-to-pin compatible package
Create a custom design using the
LMR514x5-Q1
with the
WEBENCH®
Power Designer