SLVSFF1C
December 2021 – November 2025
LM5123-Q1
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Description (continued)
5
Pin Configuration and Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Information
6.5
Electrical Characteristics
6.6
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
Device Enable/Disable (EN, VH Pin)
7.3.2
High Voltage VCC Regulator (BIAS, VCC Pin)
7.3.3
Light Load Switching Mode Selection (MODE Pin)
7.3.4
VOUT Range Selection (RANGE Pin)
7.3.5
Line Undervoltage Lockout (UVLO Pin)
7.3.6
Fast Restart Using VCC HOLD (VH Pin)
7.3.7
Adjustable Output Regulation Target (VOUT, TRK, VREF Pin)
7.3.8
Overvoltage Protection (VOUT Pin)
7.3.9
Power Good Indicator (PGOOD Pin)
7.3.10
Dynamically Programmable Switching Frequency (RT)
7.3.11
External Clock Synchronization (SYNC Pin)
7.3.12
Programmable Spread Spectrum (DITHER Pin)
7.3.13
Programmable Soft Start (SS Pin)
7.3.14
Wide Bandwidth Transconductance Error Amplifier and PWM (TRK, COMP Pin)
7.3.15
Current Sensing and Slope Compensation (CSP, CSN Pin)
7.3.16
Constant Peak Current Limit (CSP, CSN Pin)
7.3.17
Maximum Duty Cycle and Minimum Controllable On-Time Limits
7.3.18
Deep Sleep Mode and Bypass Operation (HO, CP Pin)
7.3.19
MOSFET Drivers, Integrated Boot Diode, and Hiccup Mode Fault Protection (LO, HO, HB Pin)
7.3.20
Thermal Shutdown Protection
7.4
Device Functional Modes
7.4.1
Device Status
7.4.1.1
Shutdown Mode
7.4.1.2
Configuration Mode
7.4.1.3
Active Mode
7.4.1.4
Sleep Mode
7.4.1.5
Deep Sleep Mode
7.4.2
Light Load Switching Mode
7.4.2.1
Forced PWM (FPWM) Mode
7.4.2.2
Diode Emulation (DE) Mode
7.4.2.3
Forced Diode Emulation Operation in FPWM Mode
7.4.2.4
Skip Mode
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
Application Ideas
8.2.3
Application Curves
8.3
System Example
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
11.2
Receiving Notification of Documentation Updates
11.3
Support Resources
11.4
Trademarks
11.5
Electrostatic Discharge Caution
11.6
Glossary
12
Revision History
13
Mechanical, Packaging, and Orderable Information
11.6
Glossary
TI Glossary
This glossary lists and explains terms, acronyms, and definitions.