SLUSCV5
May 2022
TPS92643-Q1
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
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
Internal Regulator
7.3.2
Buck Converter Switching Operation
7.3.3
Bootstrap Supply
7.3.4
Switching Frequency and Adaptive On-Time Control
7.3.5
Minimum On-Time, Off-Time, and Inductor Ripple
7.3.6
LED Current Regulation and Error Amplifier
7.3.7
Start-Up Sequence
7.3.8
Analog Dimming and Forced Continuous Conduction Mode
7.3.9
External PWM Dimming and Input Undervoltage Lockout (UVLO)
7.3.10
Analog Pulse Width Modulator Circuit
7.3.11
Output Short and Open-Circuit Faults
7.3.12
Overcurrent Protection
7.3.13
Thermal Shutdown
7.3.14
Fault Indicator and Diagnostics Summary
7.4
Device Functional Modes
8
Application and Implementation
8.1
Application Information
8.1.1
Duty Cycle Considerations
8.1.2
Switching Frequency Selection
8.1.3
LED Current Programming
8.1.4
Inductor Selection
8.1.5
Output Capacitor Selection
8.1.6
Input Capacitor Selection
8.1.7
Bootstrap Capacitor Selection
8.1.8
Bootstrap Resistor Selection
8.1.9
Compensation Capacitor Selection
8.1.10
Input Dropout and Undervoltage Protection
8.1.11
APWM Input and Thermal Protection
8.1.12
Protection Diodes
8.2
Typical Application
8.2.1
Design Requirements
8.2.2
Detailed Design Procedure
8.2.2.1
Calculating Duty Cycle
8.2.2.2
Calculating Minimum On-Time and Off-Time
8.2.2.3
Minimum Switching Frequency
8.2.2.4
LED Current Set Point
8.2.2.5
Inductor Selection
8.2.2.6
Output Capacitor Selection
8.2.2.7
Bootstrap Capacitor Selection
8.2.2.8
Bootstrap Resistor Selection
8.2.2.9
Compensation Capacitor Selection
8.2.2.10
VIN Dropout Protection and PWM Dimming
8.2.3
Application Curves
9
Power Supply Recommendations
10
Layout
10.1
Layout Guidelines
10.1.1
Compact Layout for EMI Reduction
10.1.1.1
Ground Plane
10.2
Layout Example
11
Device and Documentation Support
11.1
Receiving Notification of Documentation Updates
11.2
Support Resources
11.3
Trademarks
11.4
Electrostatic Discharge Caution
11.5
Glossary
12
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
PWP|16
MPDS371A
Thermal pad, mechanical data (Package|Pins)
Orderable Information
sluscv5_oa
sluscv5_pm
8.2.2.7
Bootstrap Capacitor Selection
Referring to
Table 8-2
, a standard 1-µF, 16-V X7R capacitor is selected to support PWM frequency of 200 Hz.