ZHCSOA1A July 2021 – July 2021 TPS548B27
PRODUCTION DATA
- 1 特性
- 2 应用
- 3 说明
- 4 Revision History
- 5 Pin Configuration and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3
Feature Description
- 7.3.1 Internal VCC LDO and Using External Bias on VCC Pin
- 7.3.2 Enable
- 7.3.3 Output Voltage Setting
- 7.3.4 Internal Fixed Soft Start and External Adjustable Soft Start
- 7.3.5 External REFIN For Output Voltage Tracking
- 7.3.6 Frequency and Operation Mode Selection
- 7.3.7 D-CAP3 Control
- 7.3.8 Low-Side FET Zero-Crossing
- 7.3.9 Current Sense and Positive Overcurrent Protection
- 7.3.10 Low-Side FET Negative Current Limit
- 7.3.11 Power Good
- 7.3.12 Overvoltage and Undervoltage Protection
- 7.3.13 Out-Of-Bounds (OOB) Operation
- 7.3.14 Output Voltage Discharge
- 7.3.15 UVLO Protection
- 7.3.16 Thermal Shutdown
- 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 Procedure
- 8.2.2.1 Output Voltage Setting Point
- 8.2.2.2 Choose the Switching Frequency and the Operation Mode
- 8.2.2.3 Choose the Inductor
- 8.2.2.4 Set the Current Limit (TRIP)
- 8.2.2.5 Choose the Output Capacitor
- 8.2.2.6 Choose the Input Capacitors (CIN)
- 8.2.2.7 Soft-Start Capacitor (SS/REFIN Pin)
- 8.2.2.8 EN Pin Resistor Divider
- 8.2.2.9 VCC Bypass Capacitor
- 8.2.2.10 BOOT Capacitor
- 8.2.2.11 PGOOD Pullup Resistor
- 8.2.3 Application Curves
- 9 Power Supply Recommendations
- 10布局
- 11Device and Documentation Support
- 12Mechanical, Packaging, and Orderable Information
7.4.3 Powering the Device from a 12-V Bus
The device works well when powering from a 12-V bus with a single VIN configuration. As a single VIN configuration, the internal LDO is powered by a 12-V bus and generates a 3.0-V output to bias the internal analog circuitry and powers up the gate drives. The VIN input range under this configuration is 4 V to 16 V for up to 20-A load current. Figure 7-5 shows an example for this single VIN configuration.
VIN and EN are the two signals to enable the part. For start-up sequence, any sequence between the VIN and EN signals can power the device up correctly.
Figure 7-5 Single VIN
Configuration for a 12-V Bus