ZHCSNB4
february 2023
LM5148
PRODUCTION DATA
1
特性
2
应用
3
说明
4
Revision History
5
说明(续)
6
Pin Configuration and Functions
7
Specifications
7.1
Absolute Maximum Ratings
7.2
ESD Ratings
7.3
Recommended Operating Conditions
7.4
Thermal Information
7.5
Electrical Characteristics
7.6
Typical Characteristics
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Input Voltage Range (VIN)
8.3.2
High-Voltage Bias Supply Regulator (VCC, VCCX, VDDA)
8.3.3
Precision Enable (EN)
8.3.4
Power-Good Monitor (PG)
8.3.5
Switching Frequency (RT)
8.3.6
Dual Random Spread Spectrum (DRSS)
8.3.7
Soft Start
8.3.8
Output Voltage Setpoint (FB)
8.3.9
Minimum Controllable On Time
8.3.10
Error Amplifier and PWM Comparator (FB, EXTCOMP)
8.3.11
Slope Compensation
8.3.12
Inductor Current Sense (ISNS+, VOUT)
8.3.12.1
Shunt Current Sensing
8.3.12.2
Inductor DCR Current Sensing
8.3.13
Hiccup Mode Current Limiting
8.3.14
High-Side and Low-Side Gate Drivers (HO, LO)
8.3.15
Output Configurations (CNFG)
8.3.16
Single-Output Dual-Phase Operation
8.4
Device Functional Modes
8.4.1
Sleep Mode
8.4.2
Pulse Frequency Modulation and Synchronization (PFM/SYNC)
8.4.3
Thermal Shutdown
9
Application and Implementation
9.1
Application Information
9.1.1
Power Train Components
9.1.1.1
Buck Inductor
9.1.1.2
Output Capacitors
9.1.1.3
Input Capacitors
9.1.1.4
Power MOSFETs
9.1.1.5
EMI Filter
9.1.2
Error Amplifier and Compensation
9.2
Typical Applications
9.2.1
Design 1 – High Efficiency 2.1-MHz Synchronous Buck Regulator
9.2.1.1
Design Requirements
9.2.1.2
Detailed Design Procedure
9.2.1.2.1
Custom Design with WEBENCH® Tools
9.2.1.2.2
Custom Design with Excel Quickstart Tool
9.2.1.2.3
Buck Inductor
9.2.1.2.4
Current-Sense Resistance
9.2.1.2.5
Output Capacitors
9.2.1.2.6
Input Capacitors
9.2.1.2.7
Frequency Set Resistor
9.2.1.2.8
Feedback Resistors
9.2.1.2.9
Compensation Components
9.2.1.3
Application Curves
9.2.2
Design 2 – High Efficiency 48-V to 12-V 400-kHz Synchronous Buck Regulator
9.2.2.1
Design Requirements
9.2.2.2
Detailed Design Procedure
9.2.2.3
Application Curves
9.2.3
Design 3 – High Efficiency 440-kHz Synchronous Buck Regulator
9.2.3.1
Design Requirements
9.2.3.2
Detailed Design Procedure
9.2.3.3
Application Curves
9.2.4
Design 4 – Dual-Phase 400-kHz 20-A Synchronous Buck Regulator
9.2.4.1
Design Requirements
9.2.4.2
Detailed Design Procedure
9.2.4.3
Application Curves
9.3
Power Supply Recommendations
9.4
Layout
9.4.1
Layout Guidelines
9.4.1.1
Power Stage Layout
9.4.1.2
Gate-Drive Layout
9.4.1.3
PWM Controller Layout
9.4.1.4
Thermal Design and Layout
9.4.1.5
Ground Plane Design
9.4.2
Layout Example
10
Device and Documentation Support
10.1
Device Support
10.1.1
Development Support
10.1.1.1
Custom Design with WEBENCH® Tools
10.2
Documentation Support
10.2.1
Related Documentation
10.2.1.1
PCB Layout Resources
10.2.1.2
Thermal Design Resources
10.3
接收文档更新通知
10.4
支持资源
10.5
Trademarks
10.6
静电放电警告
10.7
术语表
11
Mechanical, Packaging, and Orderable Information
封装选项
机械数据 (封装 | 引脚)
RGY|24
MPQF143E
散热焊盘机械数据 (封装 | 引脚)
RGY|24
QFND678
订购信息
zhcsnb4_oa
7.6
Typical Characteristics
V
IN
= 12 V, unless otherwise specified
V
OUT
= 5 V
F
SW
= 440 kHz
Figure 7-1
Efficiency vs Load
V
EN
= 0 V
Figure 7-3
Shutdown Current vs Temperature
V
VOUT
= 5 V
1.03 V ≤ V
EN
≤ 80 V
Figure 7-5
Sleep2 Current vs Temperature
Figure 7-7
Fixed 5-V Output Voltage vs Temperature
Figure 7-9
PG OV Thresholds vs Temperature
Figure 7-11
VCC Regulation Voltage vs Temperature
Figure 7-13
VCC Current Limit vs Temperature
Figure 7-15
VDDA UVLO Thresholds vs Temperature
Figure 7-17
Current Sense (CS) Threshold vs Temperature
Figure 7-19
Minimum On Time (HO) vs Temperature
R
RT
= 9.09 kΩ
Figure 7-21
Switching Frequency vs Temperature
V
OUT
= 5 V
F
SW
= 440 kHz
Figure 7-2
Efficiency vs Load, Log Scale
V
VOUT
= 3.3 V
1.03 V ≤ V
EN
≤ 80 V
Figure 7-4
Sleep1 Current vs Temperature
Figure 7-6
Fixed 3.3-V Output Voltage vs Temperature
Figure 7-8
Feedback Voltage vs Temperature
Figure 7-10
PG UV Thresholds vs Temperature
Figure 7-12
VCC UVLO Thresholds vs Temperature
Figure 7-14
VDDA Regulation Voltage vs Temperature
Figure 7-16
VCCX On, Off Thresholds vs Temperature
Figure 7-18
Current Sense (CS) Amplifier Gain vs Temperature
Figure 7-20
Soft-Start Time vs Temperature