JAJSM23G
December 2012 – May 2021
LM25018
PRODUCTION DATA
1
特長
2
アプリケーション
3
概要
4
Revision History
5
Pin Configuration and Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Characteristics
6.5
Electrical Characteristics
6.6
Switching Characteristics
6.7
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
Control Overview
7.3.2
VCC Regulator
7.3.3
Regulation Comparator
7.3.4
Overvoltage Comparator
7.3.5
On-Time Generator
7.3.6
Current Limit
7.3.7
N-Channel Buck Switch and Driver
7.3.8
Synchronous Rectifier
7.3.9
Undervoltage Detector
7.3.10
Thermal Protection
7.3.11
Ripple Configuration
7.3.12
Soft Start
7.4
Device Functional Modes
8
Application and Implementation
8.1
Application Information
8.2
Typical Applications
8.2.1
Application Circuit: 12.5-V to 48-V Input and 10-V, 325-mA Output Buck Converter
8.2.1.1
Design Requirements
8.2.1.2
Detailed Design Procedure
8.2.1.2.1
Custom Design With WEBENCH® Tools
8.2.1.2.2
RFB1, RFB2
8.2.1.2.3
Frequency Selection
8.2.1.2.4
Inductor Selection
8.2.1.2.5
Output Capacitor
8.2.1.2.6
Type III Ripple Circuit
8.2.1.2.7
VCC and Bootstrap Capacitor
8.2.1.2.8
Input Capacitor
8.2.1.2.9
UVLO Resistors
8.2.2
Application Curves
8.2.3
Typical Isolated DC-DC Converter Using LM25018
8.2.3.1
Design Requirements
8.2.3.2
Detailed Design Procedure
8.2.3.2.1
Transformer Turns Ratio
8.2.3.2.2
Total IOUT
8.2.3.2.3
RFB1, RFB2
8.2.3.2.4
Frequency Selection
8.2.3.2.5
Transformer Selection
8.2.3.2.6
Primary Output Capacitor
8.2.3.2.7
Secondary Output Capacitor
8.2.3.2.8
Type III Feedback Ripple Circuit
8.2.3.2.9
Secondary Diode
8.2.3.2.10
VCC and Bootstrap Capacitor
8.2.3.2.11
Input Capacitor
8.2.3.2.12
UVLO Resistors
8.2.3.2.13
VCC Diode
8.2.3.3
Application Curves
9
Power Supply Recommendations
10
Layout
10.1
Layout Guidelines
10.2
Layout Example
11
Device and Documentation Support
11.1
Device Support
11.1.1
Third-Party Products Disclaimer
11.1.2
Development Support
11.1.2.1
Custom Design With WEBENCH® Tools
11.2
Documentation Support
11.2.1
Related Documentation
11.3
Receiving Notification of Documentation Updates
11.4
サポート・リソース
11.5
Trademarks
11.6
Electrostatic Discharge Caution
11.7
Glossary
12
Mechanical, Packaging, and Orderable Information
パッケージ・オプション
メカニカル・データ(パッケージ|ピン)
DDA|8
MPDS092F
NGU|8
MPDS407A
サーマルパッド・メカニカル・データ
発注情報
jajsm23g_oa
jajsm23g_pm
8.2.3.3
Application Curves
Figure 8-9
Steady State Waveform (V
IN
= 24 V, I
OUT1
= 0 mA, I
OUT2
= 200 mA)
Figure 8-11
Efficiency at 500 kHz, V
OUT1
= 5 V
Figure 8-10
Step Load Response (V
IN
= 24 V, I
OUT1
= 0, Step Load on I
OUT2
= 100 mA to 200 mA)