SNVS726F
July 2011 – March 2018
LM25118
PRODUCTION DATA.
1
Features
2
Applications
3
Description
Device Images
Simplified Schematic
Efficiency vs VIN and IOUT, VOUT = 12 V
4
Revision History
5
Pin Configuration and Functions
Pin 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
UVLO
7.3.2
Oscillator and Sync Capability
7.3.3
Error Amplifier and PWM Comparator
7.3.4
Ramp Generator
7.3.5
Current Limit
7.3.6
Maximum Duty Cycle
7.3.7
Soft Start
7.3.8
HO Output
7.3.9
Thermal Protection
7.4
Device Functional Modes
7.4.1
Buck Mode Operation: VIN > VOUT
7.4.2
Buck-Boost Mode Operation: VIN ≊ VOUT
7.4.3
High Voltage Start-Up Regulator
7.4.4
Enable
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
R7 = RT
8.2.2.3
Inductor Selection – L1
8.2.2.4
R13 = RSENSE
8.2.2.5
C15 = CRAMP
8.2.2.6
Inductor Current Limit Calculation
8.2.2.7
C9 - C12 = Output Capacitors
8.2.2.8
D1
8.2.2.9
D4
8.2.2.10
C1 – C5 = Input Capacitors
8.2.2.11
C20
8.2.2.12
C8
8.2.2.13
C16 = CSS
8.2.2.14
R8, R9
8.2.2.15
R1, R3, C21
8.2.2.16
R2
8.2.2.17
Snubber
8.2.2.18
Error Amplifier Configuration
8.2.2.18.1
R4, C18, C17
8.2.3
Application Curves
9
Power Supply Recommendations
9.1
Bias Power Dissipation Reduction
9.2
Thermal Considerations
10
Layout
10.1
Layout Guidelines
10.2
Layout Example
11
Device and Documentation Support
11.1
Device Support
11.1.1
Development Support
11.1.1.1
Custom Design With WEBENCH® Tools
11.2
Receiving Notification of Documentation Updates
11.3
Community Resources
11.4
Trademarks
11.5
Electrostatic Discharge Caution
11.6
Glossary
12
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
PWP|20
MHTS001G
Thermal pad, mechanical data (Package|Pins)
PWP|20
PPTD289
Orderable Information
snvs726f_oa
snvs726f_pm
1
Features
Input Voltage Operating Range From 3 V to 42 V
Emulated Peak Current Mode Control
Smooth Transition Between Step-Down and Step-Up Modes
Switching Frequency Programmable to 500 KHz
Oscillator Synchronization Capability
Internal High Voltage Bias Regulator
Integrated High and Low-Side Gate Drivers
Programmable Soft-Start Time
Ultra-Low Shutdown Current
Enable Input
Wide Bandwidth Error Amplifier
1.5% Feedback Reference Accuracy
Thermal Shutdown
Package: 20-Pin HTSSOP (Exposed Pad)
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