SLUS593J
December 2003 – June 2022
TPS40054
,
TPS40055
,
TPS40057
PRODUCTION DATA
1
Features
2
Applications
3
Description
4
Revision History
5
Pin Configuration and Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
Recommended Operating Conditions
6.3
Thermal Information
6.4
Electrical Characteristics
6.5
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
Setting the Switching Frequency (Programming the Clock Oscillator)
7.3.2
Programming The Ramp Generator Circuit
7.3.3
UVLO Operation
7.3.4
BP5 and BP10 Internal Voltage Regulators
7.3.5
Programming Soft Start
7.3.6
Programming Current Limit
7.3.7
Synchronizing to an External Supply
7.3.8
Loop Compensation
7.4
Device Functional Modes
8
Application and Implementation
8.1
Application Information
8.1.1
Selecting the Inductor Value
8.1.2
Calculating the Output Capacitance
8.1.3
Calculating the Boost and BP10 Bypass Capacitor
8.1.4
DV-DT Induced Turn-On
8.1.5
High-Side MOSFET Power Dissipation
8.1.6
Synchronous Rectifier MOSFET Power Dissipation
8.1.7
TPS4005x Power Dissipation
8.2
Typical Application
8.2.1
Design Requirements
8.2.2
Detailed Design Procedure
8.2.2.1
Calculate Maximum and Minimum Duty Cycles
8.2.2.2
Select Switching Frequency
8.2.2.3
Select ΔI
8.2.2.4
Calculate the High-Side MOSFET Power Losses
8.2.2.5
Calculate Synchronous Rectifier Losses
8.2.2.6
Calculate the Inductor Value
8.2.2.7
Set the Switching Frequency
8.2.2.8
Program the Ramp Generator Circuit
8.2.2.9
Calculate the Output Capacitance (CO)
8.2.2.10
Calculate the Soft-Start Capacitor (CSS/SD)
8.2.2.11
Calculate the Current Limit Resistor (RILIM)
8.2.2.12
Calculate Loop Compensation Values
8.2.2.13
Calculate the Boost and BP10V Bypass Capacitance
8.2.3
Application Curves
9
Power Supply Recommendations
10
Layout
10.1
Layout Guidelines
10.2
Layout Example
10.3
MOSFET Packaging
11
Device and Documentation Support
11.1
Device Support
11.1.1
Third-Party Products Disclaimer
11.2
Documentation Support
11.2.1
Related Documentation
11.3
Receiving Notification of Documentation Updates
11.4
Support Resources
11.5
Trademarks
11.6
Electrostatic Discharge Caution
11.7
Glossary
12
Mechanical, Packaging, and Orderable Information
1
Features
New products available
LM5145
75-V synchronous buck controller with wide input voltage and duty cycle ranges
LM5146
100-V synchronous buck DC/DC controller with wide duty-cycle range
Operating input voltage 8 V to 40 V
Input voltage feedforward compensation
< 1% internal 0.7-V reference
Programmable fixed-frequency up to 1-MHz voltage mode controller
Internal gate-drive outputs for high-side and synchronous N-channel MOSFETs
16-pin
PowerPAD™
package (R
θJC
= 2°C/W)
Thermal shutdown
Externally synchronizable
Programmable high-side sense short-circuit protection
Programmable closed-loop soft start
TPS40054 source only
TPS40055 source and sink
TPS40057 source and sink with V
O
prebias