SLUSCV2B
June 2017 – August 2026
TPS54308
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Pin Configuration and Functions
5
Specifications
5.1
Absolute Maximum Ratings
5.2
ESD Ratings
5.3
Recommended Operating Conditions
5.4
Thermal Information
5.5
Electrical Characteristics
5.6
Timing Requirements
5.7
Typical Characteristics
6
Detailed Description
6.1
Overview
6.2
Functional Block Diagram
6.3
Feature Description
6.3.1
Fixed-Frequency PWM Control
6.3.2
Force Continuous Conduction Mode (FCCM)
6.3.3
Error Amplifier
6.3.4
Slope Compensation and Output Current
6.3.5
Enable and Adjusting Undervoltage Lockout
6.3.6
Safe Start-Up into Prebiased Outputs
6.3.7
Voltage Reference
6.3.8
Adjusting Output Voltage
6.3.9
Internal Soft Start
6.3.10
Bootstrap Voltage (BOOT)
6.3.11
Overcurrent Protection
6.3.11.1
High-Side MOSFET Overcurrent Protection
6.3.11.2
Low-Side MOSFET Overcurrent Protection
6.3.12
Output Overvoltage Protection (OVP)
6.3.13
Thermal Shutdown
6.4
Device Functional Modes
7
Application and Implementation
7.1
Application Information
7.2
Typical Application
7.2.1
TPS54308 8V to 28V Input, 5V Output Converter
7.2.2
Design Requirements
7.2.3
Detailed Design Procedure
7.2.3.1
Custom Design With WEBENCH® Tools
7.2.3.2
Input Capacitor Selection
7.2.3.3
Bootstrap Capacitor Selection
7.2.3.4
Output Voltage Set Point
7.2.3.5
Undervoltage Lockout Set Point
7.2.3.6
Output Filter Components
7.2.3.6.1
Inductor Selection
7.2.3.6.2
Output Capacitor Selection
7.2.3.6.3
Feedforward Capacitor
7.2.4
Application Curves
7.3
Power Supply Recommendations
7.4
Layout
7.4.1
Layout Guidelines
7.4.2
Layout Example
8
Device and Documentation Support
8.1
Device Support
8.1.1
Third-Party Products Disclaimer
8.1.2
Development Support
8.1.2.1
Custom Design With WEBENCH® Tools
8.2
Receiving Notification of Documentation Updates
8.3
Support Resources
8.4
Trademarks
8.5
Electrostatic Discharge Caution
8.6
Glossary
9
Revision History
10
Mechanical, Packaging, and Orderable Information
7.2.4
Application Curves
Figure 7-2
Efficiency
Figure 7-4
Load Regulation
I
OUT
= 0 A
Figure 7-6
Output Voltage Ripple
I
OUT
= 100 mA
Figure 7-8
Output Voltage Ripple
I
OUT
= 3 A
Figure 7-10
Transient Response
Figure 7-12
Start-Up Relative to VIN
Figure 7-14
Start-Up Relative to EN
Figure 7-3
Line Regulation
Figure 7-5
Input Voltage Ripple
I
OUT
= 10 mA
Figure 7-7
Output Voltage Ripple
I
OUT
= 1.5 A
Figure 7-9
Output Voltage Ripple
0.75 to 2.25A load step, slew rate = 250mA/μsec
Figure 7-11
Transient Response
Figure 7-13
Shutdown Relative to VIN
Figure 7-15
Shutdown Relative to EN