SNVSCD4
September 2024
LM70660
,
LM706A0
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Pin Configuration and Functions
5
Specifications
5.1
Absolute Maximum Ratings
5.2
ESD Ratings
5.3
Recommended Operating Conditions
5.4
Thermal Information
5.5
Electrical Characteristics
5.6
Typical Characteristics
6
Detailed Description
6.1
Overview
6.2
Functional Block Diagram
6.3
Feature Description
6.3.1
Input Voltage Range (VIN)
6.3.2
High-Voltage Bias Supply Regulator (VCC, BIAS, VDDA)
6.3.3
Enable (EN)
6.3.4
Power-Good Monitor (PG)
6.3.5
Switching Frequency (RT)
6.3.6
Dual Random Spread Spectrum (DRSS)
6.3.7
Soft Start
6.3.8
Output Voltage Setpoint (FB)
6.3.9
Minimum Controllable On-Time
6.3.10
Error Amplifier and PWM Comparator (FB, EXTCOMP)
6.3.11
Slope Compensation
6.3.12
Shunt Current Sensing
6.3.13
Hiccup Mode Current Limiting
6.3.14
Device Configuration (CONFIG)
6.3.15
Single-Output Dual-Phase Operation
6.3.16
Pulse Frequency Modulation (PFM) / Synchronization
6.3.17
Thermal Shutdown (TSD)
6.4
Device Functional Modes
6.4.1
Shutdown Mode
6.4.2
Standby Mode
6.4.3
Active Mode
6.4.4
Sleep Mode
7
Application and Implementation
7.1
Application Information
7.1.1
Power Train Components
7.1.1.1
Buck Inductor
7.1.1.2
Output Capacitors
7.1.1.3
Input Capacitors
7.1.1.4
EMI Filter
7.1.2
Error Amplifier and Compensation
7.1.3
Maximum Ambient Temperature
7.1.3.1
Derating Curves
7.2
Typical Applications
7.2.1
Design 1 – High Efficiency, Wide Input, 400kHz Synchronous Buck Regulator
7.2.1.1
Design Requirements
7.2.1.2
Detailed Design Procedure
7.2.1.2.1
Custom Design With WEBENCH® Tools
7.2.1.2.2
Custom Design With Excel Quickstart Tool
7.2.1.2.3
Buck Inductor
7.2.1.2.4
Current-Sense Resistance
7.2.1.2.5
Output Capacitors
7.2.1.2.6
Input Capacitors
7.2.1.2.7
Frequency Set Resistor
7.2.1.2.8
Feedback Resistors
7.2.1.2.9
Compensation Components
7.2.1.3
Application Curves
7.2.2
Design 2 – High Efficiency 24V to 3.3V 400kHz Synchronous Buck Regulator
7.2.2.1
Design Requirements
7.2.2.2
Detailed Design Procedure
7.2.2.3
Application Curves
7.3
Power Supply Recommendations
7.4
Layout
7.4.1
Layout Guidelines
7.4.1.1
Thermal Design and Layout
7.4.2
Layout Example
8
Device and Documentation Support
8.1
Device Support
8.1.1
Development Support
8.1.1.1
Custom Design With WEBENCH® Tools
8.2
Documentation Support
8.2.1
Related Documentation
8.2.1.1
PCB Layout Resources
8.2.1.2
Thermal Design Resources
8.3
Receiving Notification of Documentation Updates
8.4
Support Resources
8.5
Trademarks
8.6
Electrostatic Discharge Caution
8.7
Glossary
9
Revision History
10
Mechanical, Packaging, and Orderable Information
10.1
Tape and Reel Information
1
Features
Functional Safety-Capable
Documentation available to aid functional safety system design
Synchronous DC/DC converter with a versatile buck controller and robust power MOSFETs
Wide input voltage range: 4.5V to
65V
Shutdown mode current: 2.3µA
No-load I
Q
regulating
24V
to 5V:
10.4µA
1% accurate, fixed 3.3V, 5V, 12V, or adjustable outputs from 0.8V to
36V
Dual-phase operation enabling output currents up to 16A
Designed for low EMI requirements
Facilitates
CISPR 11 Class B
compliance
Pin-selectable ±8% dual-random spread spectrum reduces peak emissions
Switching frequency: 200kHz to 2.2MHz
Pin-configurable AUTO or FPWM operation
Inherent protection features for robust design
Internal hiccup-mode overcurrent protection
Enable, power good, and thermal shutdown
Internal or external loop compensation
6mm × 6mm thermally optimized, RoHS compliant, QFN-29 package with Pb-free plating
Create a custom design using the
LM706x0
with the
WEBENCH®
Power Designer