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LM25149-Q1

ACTIVE

42-V automotive synchronous buck DC/DC controller with ultra-low IQ and integrated active EMI filter

Product details

Vin (min) (V) 3.5 Vin (max) (V) 42 Vout (min) (V) 0.8 Vout (max) (V) 36 Iout (max) (A) 30 Iq (typ) (mA) 0.0095 Switching frequency (min) (kHz) 100 Switching frequency (max) (kHz) 2200 EMI features Active EMI filter, Spread Spectrum Features Adjustable current limit, Enable, Frequency synchronization, Load Disconnect, Phase Interleaving, Power good, Pre-Bias Start-Up, Spread Spectrum, Synchronous Rectification, UVLO adjustable Operating temperature range (°C) -40 to 150 Regulated outputs (#) 1 TI functional safety category Functional Safety-Capable Number of phases 2 Rating Automotive Control mode current mode Type Controller
Vin (min) (V) 3.5 Vin (max) (V) 42 Vout (min) (V) 0.8 Vout (max) (V) 36 Iout (max) (A) 30 Iq (typ) (mA) 0.0095 Switching frequency (min) (kHz) 100 Switching frequency (max) (kHz) 2200 EMI features Active EMI filter, Spread Spectrum Features Adjustable current limit, Enable, Frequency synchronization, Load Disconnect, Phase Interleaving, Power good, Pre-Bias Start-Up, Spread Spectrum, Synchronous Rectification, UVLO adjustable Operating temperature range (°C) -40 to 150 Regulated outputs (#) 1 TI functional safety category Functional Safety-Capable Number of phases 2 Rating Automotive Control mode current mode Type Controller
VQFN (RGY) 24 19.25 mm² 5.5 x 3.5
  • AEC-Q100 qualified for automotive applications:
    • Device temperature grade 1: –40°C to +125°C ambient operating temperature
  • Functional Safety-Capable
  • Two integrated EMI mitigation mechanisms
    • Active EMI Filter for enhanced EMI performance at lower frequencies
    • Selectable dual random spread spectrum (DRSS) for enhanced EMI performance across low and high-frequency bands
    • EMI reduced by an average of 25 dBµV
    • Reduces the external differential-mode input filter size by 50% and lowers systems cost
  • Versatile synchronous buck DC/DC controller
    • Wide input voltage range of 3.5 V to 42 V
    • 1% accurate, fixed 3.3 V, 5 V, 12 V, or adjustable output from 0.8 V to 36 V
    • 150°C maximum junction temperature
    • Shutdown mode current: 2.3 µA
    • No-load sleep current: 9.5 µA
    • Stackable up to two phases
  • Switching frequency from 100 kHz to 2.2 MHz
    • SYNC in and SYNC out capability
  • Inherent protection features for robust design
    • Internal hiccup-mode overcurrent protection
    • ENABLE and PGOOD functions
    • VCC, VDDA, and gate-drive UVLO protection
    • Thermal shutdown protection with hysteresis
  • Create a custom design using the LM25149-Q1 with WEBENCH Power Designer
  • AEC-Q100 qualified for automotive applications:
    • Device temperature grade 1: –40°C to +125°C ambient operating temperature
  • Functional Safety-Capable
  • Two integrated EMI mitigation mechanisms
    • Active EMI Filter for enhanced EMI performance at lower frequencies
    • Selectable dual random spread spectrum (DRSS) for enhanced EMI performance across low and high-frequency bands
    • EMI reduced by an average of 25 dBµV
    • Reduces the external differential-mode input filter size by 50% and lowers systems cost
  • Versatile synchronous buck DC/DC controller
    • Wide input voltage range of 3.5 V to 42 V
    • 1% accurate, fixed 3.3 V, 5 V, 12 V, or adjustable output from 0.8 V to 36 V
    • 150°C maximum junction temperature
    • Shutdown mode current: 2.3 µA
    • No-load sleep current: 9.5 µA
    • Stackable up to two phases
  • Switching frequency from 100 kHz to 2.2 MHz
    • SYNC in and SYNC out capability
  • Inherent protection features for robust design
    • Internal hiccup-mode overcurrent protection
    • ENABLE and PGOOD functions
    • VCC, VDDA, and gate-drive UVLO protection
    • Thermal shutdown protection with hysteresis
  • Create a custom design using the LM25149-Q1 with WEBENCH Power Designer

The LM25149-Q1 is a 42-V, ultra-low IQ synchronous buck DC/DC controller for high-current, single-output applications. The controller uses a peak current-mode control architecture for easy loop compensation, fast transient response, and excellent load and line regulation. The LM25149-Q1 can be set up in dual-phase mode with accurate current sharing for high-current applications. The device can operate with VIN as low as 3.5 V, at nearly 100% duty cycle if needed.

The LM25149-Q1 has two unique EMI reduction features: active EMI filter and dual random spread spectrum (DRSS). The active EMI filter senses any noise or ripple voltage on the DC input bus and injects an out-of-phase cancellation signal to reduce the disturbance. DRSS combines low-frequency triangular and high-frequency randomized modulations to mitigate EMI across lower and higher frequency bands, respectively. This hybrid technique aligns with the multiple resolution bandwidth (RBW) settings specified in industry-standard EMC tests.

Additional features of the LM25149-Q1 include 150°C maximum junction temperature operation, user-selectable diode emulation for lower current consumption at light-load conditions, open-drain power-good flag for fault reporting and output monitoring, precision enable input, monotonic start-up into prebiased load, integrated VCC bias supply regulator and bootstrap diode, internal 3-ms soft-start time, and thermal shutdown protection with automatic recovery.

The LM25149-Q1 controller comes in a 3.5-mm × 5.5-mm thermally enhanced, 24-pin VQFN package with wettable flank pins to facilitate optical inspection during manufacturing.

The LM25149-Q1 is a 42-V, ultra-low IQ synchronous buck DC/DC controller for high-current, single-output applications. The controller uses a peak current-mode control architecture for easy loop compensation, fast transient response, and excellent load and line regulation. The LM25149-Q1 can be set up in dual-phase mode with accurate current sharing for high-current applications. The device can operate with VIN as low as 3.5 V, at nearly 100% duty cycle if needed.

The LM25149-Q1 has two unique EMI reduction features: active EMI filter and dual random spread spectrum (DRSS). The active EMI filter senses any noise or ripple voltage on the DC input bus and injects an out-of-phase cancellation signal to reduce the disturbance. DRSS combines low-frequency triangular and high-frequency randomized modulations to mitigate EMI across lower and higher frequency bands, respectively. This hybrid technique aligns with the multiple resolution bandwidth (RBW) settings specified in industry-standard EMC tests.

Additional features of the LM25149-Q1 include 150°C maximum junction temperature operation, user-selectable diode emulation for lower current consumption at light-load conditions, open-drain power-good flag for fault reporting and output monitoring, precision enable input, monotonic start-up into prebiased load, integrated VCC bias supply regulator and bootstrap diode, internal 3-ms soft-start time, and thermal shutdown protection with automatic recovery.

The LM25149-Q1 controller comes in a 3.5-mm × 5.5-mm thermally enhanced, 24-pin VQFN package with wettable flank pins to facilitate optical inspection during manufacturing.

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Technical documentation

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Type Title Date
* Data sheet LM25149-Q1 42-V Automotive, Synchronous, Buck, DC/DC Controller with Ultra-Low IQ and Integrated Active EMI Filter datasheet (Rev. B) PDF | HTML 24 Jan 2023
White paper Time-Saving and Cost-Effective Innovations for EMI Reduction (Rev. A) PDF | HTML 28 Nov 2023
Application note How to Implement a Simple Constant Current Regulation Scheme to a PCM Based Buck PDF | HTML 16 Aug 2023
User guide LM25149-Q1 EVM User's Guide (Rev. A) PDF | HTML 29 Apr 2022
Analog Design Journal How to ensure the stability and performance of an active EMI filter PDF | HTML 01 Apr 2022
More literature Using an active EMI filter in power converters to reduce EMI filter size & cost 15 Dec 2021
More literature Advanced Power-Converter Features for Reducing EMI PDF | HTML 07 Dec 2021
More literature Advanced power-converter features to reduce EMI PPT 02 Dec 2021
Functional safety information LM25149-Q1 Functional Safety, FIT Rate, Failure Mode Distribution and Pin FMA PDF | HTML 14 Sep 2021
Certificate Automotive PPAP Documentation 18 Jun 2021
Technical article Introduction to EMI: Standards, causes and mitigation techniques PDF | HTML 21 Apr 2021
Technical article How to reduce EMI and shrink power-supply size with an integrated active EMI filte PDF | HTML 05 Apr 2021
Technical article Lowering audible noise in automotive applications with TI’s DRSS technology PDF | HTML 18 Mar 2021
Analog Design Journal The pros and cons of spread‐spectrum implementation methods in buck regulators 18 Mar 2021
Certificate LM25149-Q1EVM-2100 EU Declaration of Conformity (DoC) 17 Mar 2021
White paper 透過節省時間和成本的創新技術 降低電源中的EMI 04 Dec 2020
White paper 전원 공급 장치의 EMI 절감을 위한 시간 및 비용 효율적 혁신 04 Dec 2020

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

LM25149-Q1EVM-2100 — LM25149-Q1 5.5-V to 36-V, low IQ, synchronous buck DC/DC controller evaluation module

The LM25149-Q1EVM-2100 high-density evaluation module (EVM) is designed to showcase the performance of the LM25149-Q1 high-performance, automotive synchronous buck DC/DC buck controller. It operates over a wide input voltage range of 5.5 V to 36 V to deliver a fixed 5-V output with better than 1% (...)
User guide: PDF | HTML
Not available on TI.com
Evaluation board

LM5149-Q1EVM-400 — LM5149-Q1 evaluation module, 72-V, low-IQ, synchronous buck DC/DC controller with active EMI filter

The LM5149-Q1EVM-400 high-density evaluation module (EVM) is designed to showcase the performance of the LM5149-Q1 high-performance, automotive, synchronous buck DC/DC buck controller. The EVM operates over a wide input voltage range of 15 V to 72 V to deliver a fixed 12-V output with better than (...)

User guide: PDF | HTML
Not available on TI.com
Simulation model

LM25149-Q1 PSpice Transient Model

SNVMC96.ZIP (308 KB) - PSpice Model
Calculation tool

LM5149-LM25149DESIGN-CALC LM25149 Design Calculation Tool

Welcome to the quickstart design tool for the LM5149, LM5149-Q1 and LM25149, LM25149-Q1. This standalone tool facilitates and assists the power supply engineer with the design of a DC/DC buck regulator based on the above controller family. As such, the user can expeditiously arrive at an optimized (...)
Supported products & hardware

Supported products & hardware

Products
Buck controllers (external switch)
LM25149 42-V synchronous buck DC/DC controller with ultra-low IQ and integrated active EMI filter LM25149-Q1 42-V automotive synchronous buck DC/DC controller with ultra-low IQ and integrated active EMI filter LM5149 80-V synchronous buck DC/DC controller with ultra-low IQ and integrated active EMI filter LM5149-Q1 80-V automotive synchronous buck DC/DC controller with ultra-low IQ and integrated active EMI filter
Hardware development
Evaluation board
LM25149-Q1EVM-2100 LM25149-Q1 5.5-V to 36-V, low IQ, synchronous buck DC/DC controller evaluation module
PCB layout

LM25149-Q1EVM-2100 PCB Layout Files

SNVR501.ZIP (1990 KB)
Simulation tool

PSPICE-FOR-TI — PSpice® for TI design and simulation tool

PSpice® for TI is a design and simulation environment that helps evaluate functionality of analog circuits. This full-featured, design and simulation suite uses an analog analysis engine from Cadence®. Available at no cost, PSpice for TI includes one of the largest model libraries in the (...)
Package Pins Download
VQFN (RGY) 24 View options

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