ZHCSGB0B November 2017 – November 2020 LM5145
PRODUCTION DATA
- 1 特性
- 2 应用
- 3 说明
- 4 Revision History
- 5 Description (continued)
- 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 Input Range (VIN)
- 8.3.2 Output Voltage Setpoint and Accuracy (FB)
- 8.3.3 High-Voltage Bias Supply Regulator (VCC)
- 8.3.4 Precision Enable (EN/UVLO)
- 8.3.5 Power Good Monitor (PGOOD)
- 8.3.6 Switching Frequency (RT, SYNCIN)
- 8.3.7 Configurable Soft Start (SS/TRK)
- 8.3.8 Voltage-Mode Control (COMP)
- 8.3.9 Gate Drivers (LO, HO)
- 8.3.10 Current Sensing and Overcurrent Protection (ILIM)
- 8.3.11 OCP Duty Cycle Limiter
- 8.4 Device Functional Modes
-
9 Application and Implementation
- 9.1 Application Information
- 9.2
Typical Applications
- 9.2.1 Design 1 – 20-A High-Efficiency Synchronous Buck Regulator for Telecom Power Applications
- 9.2.2 Design 2 – High Density, 12-V, 10-A Rail With LDO Low-Noise Auxiliary Output for RF Power Applications
- 9.2.3 Design 3 – 150-W, Regulated 24-V Rail for Commercial Drone Applications With Output Voltage Tracking Feature
- 9.2.4 Design 4 – Powering a Multicore DSP From a 24-V or 48-V Rail
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
9.2.2 Design 2 – High Density, 12-V, 10-A Rail With LDO Low-Noise Auxiliary Output for RF Power Applications
Figure 9-20 shows the schematic diagram of a 400-kHz, 12-V output, 10-A synchronous buck regulator intended for RF power applications.
An auxiliary 10-V, 800-mA rail to power noise-sensitive circuits is available using the LP38798 ultra-low noise LDO as a post-regulator. The internal pull-up of the EN pin of the LP38798 facilitates direct connection to the PGOOD of the LM5145 for sequential start-up control.
Figure 9-20 Application Circuit 2 With LM5145 48-V to 12-V Synchronous Buck Regulator at 400 kHz