ZHCSMS3 December 2020 TPS54622-EP
PRODUCTION DATA
- 1 特性
- 2 应用
- 3 说明
- 4 Revision History
- 5 Pin Configurations and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3
Feature Description
- 7.3.1 Fixed-Frequency PWM Control
- 7.3.2 Continuous Current Mode Operation (CCM)
- 7.3.3 VIN and Power VIN Pins (VIN and PVIN)
- 7.3.4 Voltage Reference
- 7.3.5 Adjusting the Output Voltage
- 7.3.6 Safe Start-Up Into Prebiased Outputs
- 7.3.7 Error Amplifier
- 7.3.8 Slope Compensation
- 7.3.9 Enable and Adjusting Undervoltage Lockout
- 7.3.10 Adjustable Switching Frequency and Synchronization (RT/CLK)
- 7.3.11 Slow Start (SS/TR)
- 7.3.12 Power Good (PWRGD)
- 7.3.13 Output Overvoltage Protection (OVP)
- 7.3.14 Overcurrent Protection
- 7.3.15 Thermal Shutdown
- 7.3.16 Small Signal Model for Loop Response
- 7.3.17 Simple Small Signal Model for Peak Current Mode Control
- 7.3.18 Small Signal Model for Frequency Compensation
- 7.4 Device Functional Modes
-
8 Application and Implementation
- 8.1 Application Information
- 8.2
Typical Application
- 8.2.1 Design Requirements
- 8.2.2
Detailed Design Procedures
- 8.2.2.1 Custom Design With WEBENCH® Tools
- 8.2.2.2 Operating Frequency
- 8.2.2.3 Output Inductor Selection
- 8.2.2.4 Output Capacitor Selection
- 8.2.2.5 Input Capacitor Selection
- 8.2.2.6 Slow-Start Capacitor Selection
- 8.2.2.7 Bootstrap Capacitor Selection
- 8.2.2.8 Undervoltage Lockout Setpoint
- 8.2.2.9 Output Voltage Feedback Resistor Selection
- 8.2.2.10 Compensation Component Selection
- 8.2.2.11 Fast Transient Considerations
- 8.2.3 Application Curves
- 9 Power Supply Recommendations
- 10Layout
- 11Device and Documentation Support
- 12Mechanical, Packaging, and Orderable Information
7.4.1 Adjustable Switching Frequency (RT Mode)
To determine the RT resistance for a given switching frequency, use Equation 13 or the curve in Figure 7-8. To reduce the solution size one would set the switching frequency as high as possible, but tradeoffs of the supply efficiency and minimum controllable on-time should be considered.
Equation 13. 
Figure 7-8 RT Set Resistor vs Switching Frequency