ZHCS979F June 2012 – October 2020 TPS53318 , TPS53319
PRODUCTION DATA
- 1 特性
- 2 应用
- 3 说明
- 4 Revision History
- 5 Device Comparison Table
- 6 Pin Configuration and Functions
- 7 Specifications
-
8 Detailed Description
- 8.1 Overview
- 8.2 Functional Block Diagram
- 8.3
Feature Description
- 8.3.1 5-V LDO and VREG Start-Up
- 8.3.2 Adaptive On-Time D-CAP Control and Frequency Selection
- 8.3.3 Ramp Signal
- 8.3.4 Adaptive Zero Crossing
- 8.3.5 Output Discharge Control
- 8.3.6 Power-Good
- 8.3.7 Current Sense, Overcurrent, and Short Circuit Protection
- 8.3.8 Overvoltage and Undervoltage Protection
- 8.3.9 Redundant Overvoltage Protection (OVP)
- 8.3.10 UVLO Protection
- 8.3.11 Thermal Shutdown
- 8.3.12 Small Signal Model
- 8.3.13 External Component Selection Using All Ceramic Output Capacitors
- 8.4 Device Functional Modes
-
9 Application and Implementation
- 9.1 Application Information
- 9.2
Typical Applications
- 9.2.1
Application Using Bulk Output Capacitors, Redundant Overvoltage Protection Function (OVP) Disabled
- 9.2.1.1 Design Requirements
- 9.2.1.2
Detailed Design Procedure
- 9.2.1.2.1 Step One: Select Operation Mode and Soft-Start Time
- 9.2.1.2.2 Step Two: Select Switching Frequency
- 9.2.1.2.3 Step Three: Choose the Inductor
- 9.2.1.2.4 Step Four: Choose the Output Capacitor or Capacitors
- 9.2.1.2.5 Step Five: Determine the Value of R1 and R2
- 9.2.1.2.6 Step Six: Choose the Overcurrent Setting Resistor
- 9.2.1.3 Application Curves
- 9.2.2 Application Using Ceramic Output Capacitors, Redundant Overvoltage Protection Function (OVP) Enabled
- 9.2.1
Application Using Bulk Output Capacitors, Redundant Overvoltage Protection Function (OVP) Disabled
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
9.2.1.2.4 Step Four: Choose the Output Capacitor or Capacitors
When organic semiconductor capacitor or capacitors or specialty polymer capacitor or capacitors are used, loop stability, capacitance, and ESR should satisfy Equation 7. For jitter performance, Equation 16 is a good starting point to determine ESR.
Equation 16. 
where
- D is the duty factor
- The required output ripple slope is approximately 10 mV per tSW (switching period) in terms of VFB terminal voltage