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LM51571-Q1

ACTIVE

4-A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum

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Data sheet

LM51571-Q1

ACTIVE
Data sheet Order now

Product details

Rating Automotive Topology Boost, Flyback, SEPIC Vin (max) (V) 45 Vin (min) (V) 1.5 Vout (max) (V) 48 Vout (min) (V) 2 Features Enable, Frequency synchronization, Light Load Efficiency, Nonsynchronous rectification, Power good, Spread Spectrum, UVLO adjustable EMI features Frequency Dithering, Spread Spectrum TI functional safety category Functional Safety-Capable Operating temperature range (°C) -40 to 150 Switching frequency (min) (kHz) 100 Switching frequency (max) (kHz) 2200 Iq (typ) (µA) 670 Control mode current mode Duty cycle (max) (%) 93 Switch current limit (typ) (A) 5 Type Converter
Rating Automotive Topology Boost, Flyback, SEPIC Vin (max) (V) 45 Vin (min) (V) 1.5 Vout (max) (V) 48 Vout (min) (V) 2 Features Enable, Frequency synchronization, Light Load Efficiency, Nonsynchronous rectification, Power good, Spread Spectrum, UVLO adjustable EMI features Frequency Dithering, Spread Spectrum TI functional safety category Functional Safety-Capable Operating temperature range (°C) -40 to 150 Switching frequency (min) (kHz) 100 Switching frequency (max) (kHz) 2200 Iq (typ) (µA) 670 Control mode current mode Duty cycle (max) (%) 93 Switch current limit (typ) (A) 5 Type Converter
WQFN (RTE) 16 9 mm² 3 x 3
  • AEC-Q100 qualified for automotive applications
    • Temperature grade 1: –40°C to +125°C T A
  • Functional Safety-Capable
  • Suited for wide operating range for car battery applications
    • 2.9-V to 45-V input operating range
    • 48-V maximum output (50-V abs max)
    • Minimum boost supply voltage of 1.5 V when BIAS ≥ 2.9 V
    • Input transient protection up to 50 V
    • Minimized battery drain
      • Low shutdown current (I Q ≤ 2.6 µA)
      • Low operating current (I Q ≤ 700 µA)
  • Small solution size and low cost
    • Maximum switching frequency up to 2.2 MHz
    • 16-pin QFN package (3 mm × 3 mm) with wettable flanks
    • Integrated error amplifier allows primary-side regulation without optocoupler (flyback)
    • Minimized undershoot during cranking (start-stop application)
    • Accurate current limit (see the Device Comparison Table)
  • EMI mitigation
    • Selectable dual random spread spectrum
    • Lead-less package
  • Higher efficiency with low-power dissipation
    • 45-mΩ R DSON switch
    • Fast switching, small switching loss
  • Avoid AM band interference and crosstalk
    • Optional clock synchronization
    • Dynamically programmable wide switching frequency from 100 kHz to 2.2 MHz
  • Integrated protection features
    • Constant current limiting over input voltage
    • Selectable hiccup mode overload protection
    • Programmable line UVLO
    • OVP protection
    • Thermal shutdown
  • Accurate ±1% accuracy feedback reference
  • Adjustable soft start
  • PGOOD indicator
  • Create a custom design using the LM5157x-Q1 with the WEBENCH Power Designer
  • AEC-Q100 qualified for automotive applications
    • Temperature grade 1: –40°C to +125°C T A
  • Functional Safety-Capable
  • Suited for wide operating range for car battery applications
    • 2.9-V to 45-V input operating range
    • 48-V maximum output (50-V abs max)
    • Minimum boost supply voltage of 1.5 V when BIAS ≥ 2.9 V
    • Input transient protection up to 50 V
    • Minimized battery drain
      • Low shutdown current (I Q ≤ 2.6 µA)
      • Low operating current (I Q ≤ 700 µA)
  • Small solution size and low cost
    • Maximum switching frequency up to 2.2 MHz
    • 16-pin QFN package (3 mm × 3 mm) with wettable flanks
    • Integrated error amplifier allows primary-side regulation without optocoupler (flyback)
    • Minimized undershoot during cranking (start-stop application)
    • Accurate current limit (see the Device Comparison Table)
  • EMI mitigation
    • Selectable dual random spread spectrum
    • Lead-less package
  • Higher efficiency with low-power dissipation
    • 45-mΩ R DSON switch
    • Fast switching, small switching loss
  • Avoid AM band interference and crosstalk
    • Optional clock synchronization
    • Dynamically programmable wide switching frequency from 100 kHz to 2.2 MHz
  • Integrated protection features
    • Constant current limiting over input voltage
    • Selectable hiccup mode overload protection
    • Programmable line UVLO
    • OVP protection
    • Thermal shutdown
  • Accurate ±1% accuracy feedback reference
  • Adjustable soft start
  • PGOOD indicator
  • Create a custom design using the LM5157x-Q1 with the WEBENCH Power Designer

The LM5157x-Q1 device is a wide input range, non-synchronous boost converter with integrated 50-V, 6.5-A (LM5157-Q1) or 50-V, 4.33-A (LM51571-Q1) power switch.

The device can be used in boost, SEPIC, and flyback topologies. The device can start up from a single-cell battery with a minimum of 2.9 V. It can operate with the input supply voltage as low as 1.5 V if the BIAS pin is greater than 2.9 V.

The LM5157x-Q1 device is a wide input range, non-synchronous boost converter with integrated 50-V, 6.5-A (LM5157-Q1) or 50-V, 4.33-A (LM51571-Q1) power switch.

The device can be used in boost, SEPIC, and flyback topologies. The device can start up from a single-cell battery with a minimum of 2.9 V. It can operate with the input supply voltage as low as 1.5 V if the BIAS pin is greater than 2.9 V.
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LM5158-Q1 ACTIVE 3-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5158-Q1 has higher Vin, Vout capability

Technical documentation

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Type Title Date
* Data sheet LM5157x-Q1 2.2-MHz Wide VIN 50-V Boost/SEPIC/Flyback Converter with Dual Random Spread Spectrum datasheet (Rev. B) PDF | HTML 09 May 2023
White paper Isolated Bias Power Supply Architecture for HEV and EV Traction Inverters PDF | HTML 11 Oct 2023
Application note How to Implement the Soft Start in a Flyback PDF | HTML 10 Jul 2023
Application note How to Design an Isolated Flyback Converter Using LM5157x/LM5158x (Rev. A) PDF | HTML 16 Mar 2023
Application note Basic Calculation of a Coupled Inductor SEPIC Power Stage PDF | HTML 13 Mar 2023
Application note EMI 감소 기법, 듀얼 랜덤 확산 스펙트럼 (Rev. A) PDF | HTML 21 Nov 2022
Application note LM5157x, LM5158x를 사용하여 부스트 컨버터를 설계하는 방법 PDF | HTML 28 Oct 2022
Application note EMI Reduction Technique, Dual Random Spread Spectrum (Rev. A) 19 Oct 2022
User guide LM5157 SEPIC Evaluation Module PDF | HTML 07 Mar 2022
Functional safety information LM5157x-Q1 Functional Safety, FIT Rate, Failure Mode Distribution and Pin FMA (Rev. A) PDF | HTML 11 Feb 2022
Application note How to Design a Boost Converter Using LM5157x, LM5158x PDF | HTML 11 Nov 2021
EVM User's guide LM5157-Q1 Flyback Converter Evaluation Module PDF | HTML 04 May 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

Design & development

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

Evaluation board

LM5157EVM-BST — LM5157 boost converter evaluation module

The LM5157EVM-BST evaluation module showcases the features and performance of the LM5157 device as a wide input voltage boost converter with dual random spread spectrum. The standard configuration is designed to provide a regulated output of 12 V at 1.6 A from an input of 3 V to (...)
User guide: PDF | HTML
Not available on TI.com
Evaluation board

LM5157EVM-FLY — LM5157 flyback boost converter evaluation module

The LM5157EVM-FLY evaluation module showcases the features and performance of the LM5157 as a flyback converter to produce multiple output voltage rails for typical applications of the 3phase inverter gate driver bias supplies.  The standard configuration is designed to provide a regulated (...)
User guide: PDF | HTML
Not available on TI.com
Evaluation board

LM5157EVM-SEPIC — LM5157 evaluation module for SEPIC

The LM5157EVM-SEPIC evaluation module showcases the features and performance of the LM5157 as wide input non-synchronous SEPIC converter. The standard configuration is designed to provide a regulated output of 12 V at up to 1 A from an input of 4 V to 32 V, switching at 2.1 MHz.

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

LM5157x-Q1 Encrypted PSpice Transient Model (Rev. B)

SNVMC64B.ZIP (193 KB) - PSpice Model
Download
Simulation model

LM5157x-Q1 PSpice Average Model (Encrypted)

SNVMC63.ZIP (53 KB) - PSpice Model
Download
Calculation tool

SNVR508 — LM515x Quickstart Calculator for Flyback Regulator Design

Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC converters (integrated FET)
LM5157 — 6A/4A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5157-Q1 — 6-A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM51571-Q1 — 4-A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5158 — 3-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5158-Q1 — 3-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM51581 — 1.5-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM51581-Q1 — 1.5-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum
Hardware development
Evaluation board
LM5158EVM-FLY — LM5158-Q1 flyback converter evaluation module
Download
Calculation tool

SNVR511 — LM5157 and LM5158 Quickstart Calculator for Boost Regulator Design

Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC converters (integrated FET)
LM5157 — 6A/4A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5157-Q1 — 6-A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM51571-Q1 — 4-A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5158 — 3-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5158-Q1 — 3-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM51581 — 1.5-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM51581-Q1 — 1.5-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum
Download
Calculation tool

SNVR512 — LM5157 and LM5158 Quickstart Calculator for SEPIC Regulator Design

Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC converters (integrated FET)
LM5157 — 6A/4A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5157-Q1 — 6-A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM51571-Q1 — 4-A, 50-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5158 — 3-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM5158-Q1 — 3-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM51581 — 1.5-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum LM51581-Q1 — 1.5-A, 85-V, 2.2-MHz wide VIN boost, flyback, & SEPIC converter with dual random spread spectrum
Download
Package Pins CAD symbols, footprints & 3D models
WQFN (RTE) 16 Ultra Librarian
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