SLVSAA4G
June 2010 – February 2018
TPS65251
PRODUCTION DATA.
1
Features
2
Applications
3
Description
Device Images
Typical Application Schematic
4
Revision History
5
Description (continued)
6
Pin Configuration and Functions
Pin Functions
7
Specifications
7.1
Absolute Maximum Ratings
7.2
ESD Ratings
7.3
Recommended Operating Conditions
7.4
Thermal Information
7.5
Electrical Characteristics
7.6
Typical Characteristics
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Adjustable Switching Frequency
8.3.2
Synchronization
8.3.3
Out-of-Phase Operation
8.3.4
Delayed Start-Up
8.3.5
Soft-Start Time
8.3.6
Adjusting the Output Voltage
8.3.7
Input Capacitor
8.3.8
Bootstrap Capacitor
8.3.9
Error Amplifier
8.3.10
Loop Compensation
8.3.11
Slope Compensation
8.3.12
Powergood
8.3.13
Current Limit Protection
8.3.14
Overvoltage Transient Protection
8.3.15
Thermal Shutdown
8.4
Device Functional Modes
8.4.1
Low-Power Mode Operation
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
Loop Compensation Circuit
9.2.2.2
Selecting the Switching Frequency
9.2.2.3
Output Inductor Selection
9.2.2.4
Output Capacitor
9.2.2.5
Input Capacitor
9.2.2.6
Soft-Start Capacitor
9.2.2.7
Bootstrap Capacitor Selection
9.2.2.8
Adjustable Current Limiting Resistor Selection
9.2.2.9
Output Voltage and Feedback Resistors Selection
9.2.2.10
Compensation
9.2.2.11
3.3-V and 6.5-V LDO Regulators
9.2.3
Application Curves
10
Power Supply Recommendations
11
Layout
11.1
Layout Guidelines
11.2
Layout Example
11.3
Power Dissipation
12
Device and Documentation Support
12.1
Receiving Notification of Documentation Updates
12.2
Community Resources
12.3
Trademarks
12.4
Electrostatic Discharge Caution
12.5
Glossary
13
Mechanical, Packaging, and Orderable Information
1
Features
Wide Input Supply Voltage Range (4.5 to 18 V)
0.8 V, 1% Accuracy Reference
Continuous Loading: 3 A (Buck 1),
2 A (Buck 2 and 3)
Maximum Current: 3.5 A (Buck 1),
2.5 A (Buck 2 and 3)
Adjustable Switching Frequency
300 kHz to 2.2 MHz Set by External Resistor
Dedicated Enable for Each Buck
External Synchronization Pin for Oscillator
External Enable/Sequencing and Soft-Start Pins
Adjustable Current Limit Set By External Resistor
Soft-Start Pins
Current-Mode Control With Simple Compensation Circuit
Powergood
Optional Low-Power Mode Operation for Light Loads
VQFN Package, 40-Pin 6 mm × 6 mm RHA