SNVSCH2A
September 2024 – May 2025
LM65625-Q1
,
LM65635-Q1
,
LM65645-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
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
Output Voltage Selection
7.3.2
EN Pin and Use as VIN UVLO
7.3.3
Mode Selection
7.3.3.1
MODE/SYNC Pin Uses for Synchronization
7.3.3.2
Clock Locking
7.3.4
Adjustable Switching Frequency
7.3.5
Dual Random Spread Spectrum (DRSS)
7.3.6
Internal LDO, VCC UVLO, and BIAS Input
7.3.7
Bootstrap Voltage (BST Pin)
7.3.8
Soft Start and Recovery From Dropout
7.3.9
Safety Features
7.3.9.1
Power-Good Monitor
7.3.9.2
Overcurrent and Short-Circuit Protection
7.3.9.3
Hiccup
7.3.9.4
Thermal Shutdown
7.4
Device Functional Modes
7.4.1
Shutdown Mode
7.4.2
Active Mode
7.4.2.1
Peak Current Mode Operation
7.4.2.2
Auto Mode Operation
7.4.2.2.1
Diode Emulation
7.4.2.3
FPWM Mode Operation
7.4.2.4
Dropout
7.4.2.5
Recovery from Dropout
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
Choosing the Switching Frequency
8.2.2.3
FB for Adjustable or Fixed Output Voltage Mode
8.2.2.4
Inductor Selection
8.2.2.5
Output Capacitor Selection
8.2.2.6
Input Capacitor Selection
8.2.2.7
CBOOT
8.2.2.8
External UVLO
8.2.2.9
Maximum Ambient Temperature
8.2.3
Application Curves
8.3
Best Design Practices
8.4
Power Supply Recommendations
8.5
Layout
8.5.1
Layout Guidelines
8.5.1.1
Ground and Thermal Considerations
8.5.2
Layout Example
9
Device and Documentation Support
9.1
Device Support
9.1.1
Third-Party Products Disclaimer
9.1.2
Development Support
9.1.2.1
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
Package Options
Mechanical Data (Package|Pins)
RZT|20
MPQF684B
Thermal pad, mechanical data (Package|Pins)
Orderable Information
snvsch2a_oa
snvsch2a_pm
1
Features
AEC-Q100 qualified for automotive applications:
Temperature grade 1: –40°C to +125°C, T
A
Wide input voltage range: 3V to
65V (70V transient < 100ms)
Meets LV148 / ISO21780 requirements
Designed for low EMI requirements
Facilitates
CISPR 25 class 5
compliance
Mode pin configurable ±5% or ±10% dual-random spread spectrum reducing peak emissions
Enhanced
HotRod™
QFN package with symmetrical pinout
Switching frequency from 300kHz to 2.2MHz
Pin-configurable AUTO or FPWM operation
Internal compensation, current limit, and TSD
Low minimum on time: 40ns (maximum)
Enables 36V
IN
to 3.3V
OUT
conversion at 2.2MHz
High-efficiency power conversion at all loads
> 94% peak efficiency at 24V
IN
, 5V
OUT
, 400kHz
2.5µA switching input current at no load
High power density
3.6mm × 2.6mm, wettable flank, 20-pin package
Pin compatible with 36V LM654x0-Q1
ϴ
JA
= 24.0°C/W (
LM65645-Q1EVM
)
Create a custom design using the
LM656x5-Q1
with the
WEBENCH®
Power Designer