Datasheet LM25149-Q1 (Texas Instruments)

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LM25149-Q1 www.ti.com
SNVSBV6 – DECEMBER 2020
LM25149-Q1
SNVSBV6 – DECEMBER 2020
LM25149-Q1 42-V Automotive Synchronous Buck DC/DC Controller with Ultra-Low IQ and Integrated Active EMI Filter 1 Features 2 Applications
• AEC-Q100 qualified for automotive applications: • Automotive electronic systems – Device temperature grade 1: –40°C to +125°C • Infotainment systems, instrument clusters, ADAS ambient operating temperature • High-voltage battery-operated systems • Two integrated EMI mitigation mechanisms
3 Description
– Active EMI filter for enhanced EMI performance at lower frequencies The LM25149-Q1 is a 42-V synchronous buck DC/DC – Dual random spread spectrum (DRSS) for controller for high-current single-output applications. enhanced EMI performance across low and Refer to the Errata. The device uses peak current- high-frequency bands mode control architecture for easy loop – EMI reduced by an average of 25 dBµV compensation, fast transient response, and excellent load and line regulation. The LM25149-Q1 can be set
TION
– Reduces the external differential-mode filter up in interleaved mode (paralleled output) with size by 50% and lowers systems cost accurate current sharing for high-current applications.
MA
• Versatile synchronous buck DC/DC controller The LM25149-Q1 can operate at input voltages as
R
– Wide input voltage range of 3.5 V to 42 V low as 3.5 V, at nearly 100% duty cycle if needed. – 1% accurate, fixed 3.3-V, 5-V, 12-V, or adjustable outputs from 0.8 V to 36 V The LM25149-Q1 has two unique EMI reduction features: active EMI filter and Dual Random Spread – 150°C maximum junction temperature Spectrum (DRSS). Active EMI filter senses any noise – Shutdown mode current: 2.2 µA or ripple voltage on the DC input bus and injects an – No-load standby current: 9 µA out-of-phase cancellation signal to reduce the noise or • Switching frequency from 100 kHz to 2.2 MHz ripple voltage. DRSS combines a low-frequency
NCE INFO
– SYNC in and SYNC out capability triangular and high-frequency random modulation to
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• Inherent protection features for robust design optimize EMI preformance in the low-frequency and
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– Internal hiccup-mode overcurrent protection high-frequency radio frequency bands. – ENABLE and PGOOD functions
AD Device Information
– VCC, VDDA, and gate-drive UVLO protection
PART NUMBER PACKAGE(1) BODY SIZE (NOM)
– Internal or external loop compensation LM25149-Q1 VQFN (24) 3.5 mm × 5.5 mm – Thermal shutdown protection with hysteresis (1) For all available packages, see the orderable addendum at • Create a custom design using the LM25149-Q1 the end of the data sheet with WEBENCH® Power Designer
Start 150 kHz Pe CI ak SPR 25 Class 5 Peak Stop 30 MHz A CI ver SPR age 25 Class 5 Average Typical Application Schematic CISPR 25 EMI Performance 150 kHz - 30 MHz
Copyright © 2020 Texas Instruments Incorporated An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty Submit Document Feedback , changes, use in safety-critical applications, 1 intellectual property matters and other important disclaimers. ADVANCE INFORMATION for preproduction products; subject to change without notice. Product Folder Links: LM25149-Q1 Document Outline 1 Features 2 Applications 3 Description Table of Contents 4 Revision History 5 Description (continued) 6 Pin Configuration and Functions 6.1 Wettable Flanks 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 Active EMI Filter 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 Enable (EN) 8.3.4 Power Good Monitor (PG) 8.3.5 Switching Frequency (RT) 8.3.6 Active EMI Filter 8.3.7 Dual Random Spread Spectrum (DRSS) 8.3.8 Soft-Start 8.3.9 Output Voltage Setpoint (FB) 8.3.10 Minimum Controllable On-Time 8.3.11 Error Amplifier and PWM Comparator (FB, EXTCOMP) 8.3.12 Slope Compensation 8.3.13 Inductor Current Sense (ISNS+, VOUT) 8.3.13.1 Shunt Current Sensing 8.3.13.2 Inductor DCR Current Sensing 8.3.14 Hiccup Mode Current Limiting 8.3.15 High-Side and Low-Side Gate Drivers (HO, LO) 8.3.16 Output Configurations (CNFG) 8.3.17 Single-Output Two-phase Operation 8.4 Device Functional Modes 8.4.1 Standby Modes 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 Application 9.2.1 Design Requirements 9.2.2 Detailed Design Procedure 9.2.2.1 Custom Design With WEBENCH® Tools 9.2.2.2 Custom Design With Excel Quickstart Tool 9.2.2.3 Buck Inductor 9.2.2.4 Current-Sense Resistance 9.2.2.5 Output Capacitors 9.2.2.6 Input Capacitors 9.2.2.7 Frequency Set Resistor 9.2.2.8 Feedback Resistors 9.2.2.9 Compensation Components 9.2.2.10 Active EMI Components 9.2.3 Application Curves 10 Power Supply Recommendations 11 Layout 11.1 Layout Guidelines 11.1.1 Power Stage Layout 11.1.2 Gate-Drive Layout 11.1.3 PWM Controller Layout 11.1.4 Active EMI Layout 11.1.5 Thermal Design and Layout 11.1.6 Ground Plane Design 11.2 Layout Example 12 Device and Documentation Support 12.1 Device Support 12.1.1 Development Support 12.1.2 Custom Design With WEBENCH® Tools 12.2 Documentation Support 12.2.1 Related Documentation 12.2.1.1 PCB Layout Resources 12.2.1.2 Thermal Design Resources 12.3 Receiving Notification of Documentation Updates 12.4 Support Resources 12.5 Trademarks 12.6 Electrostatic Discharge Caution 12.7 Glossary 13 Mechanical, Packaging, and Orderable Information