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LM51551

ACTIVE

2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with hiccup

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Data sheet

LM51551

ACTIVE
Data sheet Order now

Product details

Rating Catalog Topology Boost, Flyback, SEPIC Vin (max) (V) 45 Vin (min) (V) 1.5 Vout (max) (V) 300 Vout (min) (V) 1.5 Features Adjustable current limit, Frequency synchronization, Hiccup mode protection, Nonsynchronous rectification, Power good, UVLO adjustable Operating temperature range (°C) -40 to 125 Iq (typ) (µA) 450 Duty cycle (max) (%) 93 TI functional safety category Functional Safety-Capable
Rating Catalog Topology Boost, Flyback, SEPIC Vin (max) (V) 45 Vin (min) (V) 1.5 Vout (max) (V) 300 Vout (min) (V) 1.5 Features Adjustable current limit, Frequency synchronization, Hiccup mode protection, Nonsynchronous rectification, Power good, UVLO adjustable Operating temperature range (°C) -40 to 125 Iq (typ) (µA) 450 Duty cycle (max) (%) 93 TI functional safety category Functional Safety-Capable
WSON (DSS) 12 6 mm² 3 x 2
  • Functional Safety-Capable
    • Documentation available to aid functional safety system design
  • Wide input operating range for battery applications
    • 3.5-V to 45-V operating range
    • 2.97-V to 16-V when BIAS = VCC
    • Minimum boost supply voltage 1.5 V when BIAS ≥ 3.5 V
    • Input transient protection up to 50 V
  • Minimized battery drain
    • Low shutdown current (I Q ≤ 2.6 µA)
    • Low operating current (I Q ≤ 480 µA)
  • Small solution size and low cost
    • Maximum switching frequency of 2.2 MHz
    • 12-Pin WSON package (3 mm × 2 mm)
    • Integrated error amplifier allows primary-side regulation without optocoupler (flyback)
    • Minimized undershoot during cranking (start-stop application)
  • Higher efficiency with low-power dissipation
    • 100-mV ±7% Low current limit threshold
    • Strong 1.5-A peak standard MOSFET driver
    • Supports external VCC supply
  • Avoid AM band interference and crosstalk
    • Optional clock synchronization
    • Dynamically programmable switching frequency from 100 kHz to 2.2 MHz
  • Integrated protection features
    • Constant peak current limiting over input voltage
    • Optional hiccup mode short-circuit protection (see the Device Comparison Table)
    • Programmable line UVLO
    • OVP protection
    • Thermal shutdown
  • Accurate ±1% accuracy feedback reference
  • Programmable extra slope compensation
  • Adjustable soft start
  • PGOOD indicator
  • Create a custom design using the LM5155x with the WEBENCH power designer
  • Functional Safety-Capable
    • Documentation available to aid functional safety system design
  • Wide input operating range for battery applications
    • 3.5-V to 45-V operating range
    • 2.97-V to 16-V when BIAS = VCC
    • Minimum boost supply voltage 1.5 V when BIAS ≥ 3.5 V
    • Input transient protection up to 50 V
  • Minimized battery drain
    • Low shutdown current (I Q ≤ 2.6 µA)
    • Low operating current (I Q ≤ 480 µA)
  • Small solution size and low cost
    • Maximum switching frequency of 2.2 MHz
    • 12-Pin WSON package (3 mm × 2 mm)
    • Integrated error amplifier allows primary-side regulation without optocoupler (flyback)
    • Minimized undershoot during cranking (start-stop application)
  • Higher efficiency with low-power dissipation
    • 100-mV ±7% Low current limit threshold
    • Strong 1.5-A peak standard MOSFET driver
    • Supports external VCC supply
  • Avoid AM band interference and crosstalk
    • Optional clock synchronization
    • Dynamically programmable switching frequency from 100 kHz to 2.2 MHz
  • Integrated protection features
    • Constant peak current limiting over input voltage
    • Optional hiccup mode short-circuit protection (see the Device Comparison Table)
    • Programmable line UVLO
    • OVP protection
    • Thermal shutdown
  • Accurate ±1% accuracy feedback reference
  • Programmable extra slope compensation
  • Adjustable soft start
  • PGOOD indicator
  • Create a custom design using the LM5155x with the WEBENCH power designer

The LM5155x (LM5155 and LM51551) is a wide input range, non-synchronous boost controller that uses peak current mode control. The device can be used in boost, SEPIC, and flyback topologies.

The LM5155x can start up from a 1-cell battery with a minimum of 2.97 V if the BIAS pin is connected to the VCC pin. It can operate with the input supply voltage as low as 1.5 V if the BIAS pin is greater than 3.5 V.

The LM5155x (LM5155 and LM51551) is a wide input range, non-synchronous boost controller that uses peak current mode control. The device can be used in boost, SEPIC, and flyback topologies.

The LM5155x can start up from a 1-cell battery with a minimum of 2.97 V if the BIAS pin is connected to the VCC pin. It can operate with the input supply voltage as low as 1.5 V if the BIAS pin is greater than 3.5 V.
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Pin-for-pin with same functionality to the compared device
LM5155 ACTIVE 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller This product does not include hiccup protection mode.
Same functionality with different pin-out to the compared device
LM51561H ACTIVE 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with spread spectrum and hiccup Includes a higher operating input voltage up to 60 V with spread spectrum and an HTSSOP package.

Technical documentation

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Type Title Date
* Data sheet LM5155x 2.2-MHz Wide Input Nonsynchronous Boost, SEPIC, Flyback Controller datasheet (Rev. E) PDF | HTML 09 May 2023
Technical article SEPIC 절연 PDF | HTML 22 Mar 2024
Technical article 부스트 컨버터로 더 많은 부스트 얻기 PDF | HTML 22 Mar 2024
Technical article 讓升壓轉換器發揮更大效用 PDF | HTML 20 Mar 2024
Technical article 隔離 SEPIC PDF | HTML 20 Mar 2024
Technical article Isolating a SEPIC PDF | HTML 26 Feb 2024
Technical article Get more boost from your boost converter PDF | HTML 21 Dec 2023
More literature LM5155x 2.2MHz 넓은 입력 비동기식 부스트, SEPIC, 플라이백 컨트롤러 (Rev. E) PDF | HTML 09 Oct 2023
Application note How to Implement the Soft Start in a Flyback PDF | HTML 10 Jul 2023
Application note LM5155를 사용하여 절연 플라이백을 설계하는 방법 (Rev. A) PDF | HTML 06 Feb 2023
Application note Programmable ±HV Power Supply With Low Static Power Consumption for Smart Probe PDF | HTML 19 Sep 2022
Application note How to Design an Isolated Flyback Using LM5155 (Rev. A) PDF | HTML 05 Jan 2021
Functional safety information LM5155x FIT Rate and Failure Mode Distribution 04 Feb 2020
Application note How to Design a Boost Converter Using LM5155 17 Dec 2018

Design & development

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

Evaluation board

LM5155EVM-BST — LM5155 Boost Controller Evaluation Module

The LM5155EVM-BST evaluation module showcases the features and performance of the LM5155, wide input non-synchronous boost controller. The standard configuration is designed to provide a regulate output of 24V at 2A from an input of 6V to 18V, switching at 440 kHz.

This EVM is designed for ease of (...)

User guide: PDF
Not available on TI.com
Evaluation board

LM5155EVM-FLY — LM5155 Flyback Controller Evaluation Module

The LM5155EVM-FLY evaluation module showcases the features and performance of the LM5155 as a wide input non-synchronous flyback controller. The standard configuration is designed to provide a regulated output of 5V at 4A from an input of 18V to 36V, switching at 250 kHz. This evaluation module is (...)
User guide: PDF
Not available on TI.com
Evaluation board

LM5155EVM-SEPIC — LM5155 SEPIC evaluation module

The LM5155EVM-SEPIC evaluation module showcases the features and performance of the LM5155 as wide input non-synchronous SEPIC controller. The standard configuration is designed to provide a regulated output of 12V at up to 2A from an input of 3V to 42V, switching at 2.2 MHz.
User guide: PDF | HTML
Not available on TI.com
Simulation model

LM5155-Q1 PSpice Transient Model (unencrypted) (Rev. F)

SNVMBL2F.ZIP (204 KB) - PSpice Model
Download
Simulation model

LM5155-Q1 PSpice Transient Model (unencrypted) (Rev. H)

SNVMBL2H.ZIP (206 KB) - PSpice Model
Download
Simulation model

LM5155-Q1 TINA-TI STARTUP REFERENCE DESIGN

SNVMBV8.TSC (1162 KB) - TINA-TI Reference Design
Download
Simulation model

LM5155-Q1 TINA-TI TRANSIENT SPICE MODEL

SNVMBV7.ZIP (52 KB) - TINA-TI Spice Model
Download
Simulation model

Unencrypted LM5155-Q1 PSpice Average Model (Rev. B)

SNVMBY3B.ZIP (81 KB) - PSpice Model
Download
Calculation tool

SNVC224 — LM5155/56 Boost Controller Quick Start Calculator

Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC controllers (external FET)
  • LM5155 — 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller
  • LM5155-Q1 — 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller, AEC-Q100 qualified
  • LM51551 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with hiccup
  • LM51551-Q1 — 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller, hiccup mode protection
  • LM5156 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
  • LM5156-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
  • LM51561 — 2.2MHz Wide Input Nonsynchronous Boost,SEPIC,Flyback Controller with Spread Spectrum
  • LM51561-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with spread spectrum and hiccup
  • LM5156H — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
  • LM5156H-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
Hardware development
Evaluation board
Download
Calculation tool

SNVC240 — LM5155/56 Flyback Controller Quick Start Calculator

LM5155/56 Flyback Controller Quick Start Calculator
Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC controllers (external FET)
  • LM5155 — 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller
  • LM5155-Q1 — 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller, AEC-Q100 qualified
  • LM51551 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with hiccup
  • LM51551-Q1 — 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller, hiccup mode protection
  • LM5156 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
  • LM5156-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
  • LM51561 — 2.2MHz Wide Input Nonsynchronous Boost,SEPIC,Flyback Controller with Spread Spectrum
  • LM51561-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with spread spectrum and hiccup
  • LM51561H — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with spread spectrum and hiccup
  • LM51561H-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with spread spectrum and hiccup
  • LM5156H — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
  • LM5156H-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
Hardware development
Evaluation board
Download
Calculation tool

SNVR481 — LM5155/56 SEPIC Controller Quick Start Calculator

Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC controllers (external FET)
  • LM5155 — 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller
  • LM5155-Q1 — 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller, AEC-Q100 qualified
  • LM51551 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with hiccup
  • LM51551-Q1 — 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller, hiccup mode protection
  • LM5156 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
  • LM5156-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
  • LM51561 — 2.2MHz Wide Input Nonsynchronous Boost,SEPIC,Flyback Controller with Spread Spectrum
  • LM51561-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with spread spectrum and hiccup
  • LM5156H — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
  • LM5156H-Q1 — 2.2-MHz wide VIN nonsynchronous boost, flyback, & SEPIC controller with dual random spread spectrum
Hardware development
Evaluation board
Download
Reference designs

PMP22800 — 24V, 1.2A DC/DC flyback reference design

This reference design uses the LM51551 as a secondary side regulated (SSR) flyback controller. It converts an input of 8 to 28.8 V and 24 V at a maximum power of 28.8 W. The supply starts up at a minimum input of 15.5 V and can operate to 8-V input. The design also includes the synchronous buck (...)
Test report: PDF
Reference designs

PMP22764 — Isolated flyback converter (24-V to 56-V/1.25-A) reference design

This reference design utilizes a diode rectified flyback converter for a 24-V input to isolated 56-V/1.25-A output. The LM51551 PWM controller provides the control for the flyback converter, including hiccup mode short circuit protection. This reference design is ideal for when any well-regulated (...)
Test report: PDF
Schematic: PDF
Reference designs

PMP30805 — Tiny automotive SEPIC reference design

This tiny automotive SEPIC reference design contains a 6-W auxiliary power supply and is designed for a 12-V bias rail. The wide input accepts cranking down to 4.5 Vmin and surge up to 40 Vmax. Due to switching frequency of 2 MHz, the dual inductor is fairly small, resulting in excellent dynamic (...)
Test report: PDF
Schematic: PDF
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WSON (DSS) 12 Ultra Librarian
TI's Standard Terms and Conditions for Evaluation Items apply.

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  • Ongoing reliability monitoring
Information included:
  • Fab location
  • Assembly location

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