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LMS3655-Q1

ACTIVE

5.5-A, 36-V synchronous, 400-kHz, step-down converter

A newer version of this product is available

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Same functionality with different pin-out to the compared device
LM61460-Q1 ACTIVE Automotive 3-V to 36-V, 6-A, low-noise synchronous step-down converter Smaller solution size, higher efficiency and lower EMI.

Product details

Vin (min) (V) 3.5 Vin (max) (V) 42 Vout (min) (V) 1 Vout (max) (V) 15 Iout (max) (A) 5.5 Iq (typ) (mA) 0.015 Switching frequency (min) (kHz) 250 Switching frequency (max) (kHz) 500 EMI features Low parasitic Hotrod packaging, Spread Spectrum Features Enable, Fixed Output, Forced PWM, Frequency synchronization, Light Load Efficiency, Over Current Protection, Power good, Pre-Bias Start-Up, Soft Start Fixed, Spread Spectrum, Synchronous Rectification, Wettable flanks package Operating temperature range (°C) -40 to 150 Rating Automotive Regulated outputs (#) 1 Control mode current mode Duty cycle (max) (%) 98 Type Converter
Vin (min) (V) 3.5 Vin (max) (V) 42 Vout (min) (V) 1 Vout (max) (V) 15 Iout (max) (A) 5.5 Iq (typ) (mA) 0.015 Switching frequency (min) (kHz) 250 Switching frequency (max) (kHz) 500 EMI features Low parasitic Hotrod packaging, Spread Spectrum Features Enable, Fixed Output, Forced PWM, Frequency synchronization, Light Load Efficiency, Over Current Protection, Power good, Pre-Bias Start-Up, Soft Start Fixed, Spread Spectrum, Synchronous Rectification, Wettable flanks package Operating temperature range (°C) -40 to 150 Rating Automotive Regulated outputs (#) 1 Control mode current mode Duty cycle (max) (%) 98 Type Converter
VQFN-HR (RNL) 22 20 mm² 5 x 4
  • AEC-Q100-qualified for automotive applications
    • Device temperature grade 1: –40°C to +125°C ambient operating temperature
    • Device HBM classification level 2
    • Device CDM classification level C6
  • 96% Peak efficiency while converting 12 V to 5 V
  • Low EMI and minimized switch node ringing
  • 400-kHz (±10%) fixed switching frequency
  • –40°C to +150°C junction temperature range
  • External frequency synchronization
  • RESET output with internal filter and 3-ms release timer
  • Automatic light load mode for improved efficiency
  • Pin-selectable forced PWM mode
  • Built-In compensation, soft start, current limit, thermal shutdown, and UVLO
  • 0.35-V dropout with 3.5-A Load at 25°C (Typical)
  • 18-µA IQ_VIN: quiescent current at 3.3 VOUT and no load (typical)
  • Output voltage: 5 V, 3.3 V, and ADJ (1 V to 20 V)
  • ±1.5% reference voltage tolerance
  • Create a custom design using the LMS3655-Q1 with the WEBENCH Power Designer
  • AEC-Q100-qualified for automotive applications
    • Device temperature grade 1: –40°C to +125°C ambient operating temperature
    • Device HBM classification level 2
    • Device CDM classification level C6
  • 96% Peak efficiency while converting 12 V to 5 V
  • Low EMI and minimized switch node ringing
  • 400-kHz (±10%) fixed switching frequency
  • –40°C to +150°C junction temperature range
  • External frequency synchronization
  • RESET output with internal filter and 3-ms release timer
  • Automatic light load mode for improved efficiency
  • Pin-selectable forced PWM mode
  • Built-In compensation, soft start, current limit, thermal shutdown, and UVLO
  • 0.35-V dropout with 3.5-A Load at 25°C (Typical)
  • 18-µA IQ_VIN: quiescent current at 3.3 VOUT and no load (typical)
  • Output voltage: 5 V, 3.3 V, and ADJ (1 V to 20 V)
  • ±1.5% reference voltage tolerance
  • Create a custom design using the LMS3655-Q1 with the WEBENCH Power Designer

The LMS3635-Q1 and LMS3655-Q1 synchronous buck regulators are optimized for high performance applications, providing an output voltage of 3.3 V, 5 V, or an adjustable output of 1 V to 20 V. Seamless transition between PWM and PFM modes, along with a low quiescent current, ensures high efficiency and superior transient responses at all loads.

Advanced high-speed circuitry allows the LMS3655-Q1 to regulate an input of 24 V to an output of 3.3 V at a fixed frequency of 400 kHz while also enabling a continuous load current of 5.5 A. An innovative frequency foldback architecture allows this device to regulate a 3.3-V output from an input voltage of only 3.5 V. The input voltage can range up to 36 V, with transient tolerance up to 42 V, easing input surge protection design.

An open-drain reset output, with built-in filtering and delay, provides a true indication of system status. This feature negates the requirement for an additional supervisory component, saving cost and board space.

The LMS3635-Q1 and LMS3655-Q1 synchronous buck regulators are optimized for high performance applications, providing an output voltage of 3.3 V, 5 V, or an adjustable output of 1 V to 20 V. Seamless transition between PWM and PFM modes, along with a low quiescent current, ensures high efficiency and superior transient responses at all loads.

Advanced high-speed circuitry allows the LMS3655-Q1 to regulate an input of 24 V to an output of 3.3 V at a fixed frequency of 400 kHz while also enabling a continuous load current of 5.5 A. An innovative frequency foldback architecture allows this device to regulate a 3.3-V output from an input voltage of only 3.5 V. The input voltage can range up to 36 V, with transient tolerance up to 42 V, easing input surge protection design.

An open-drain reset output, with built-in filtering and delay, provides a true indication of system status. This feature negates the requirement for an additional supervisory component, saving cost and board space.

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Design & development

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Evaluation board

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

LMS3655MQEVM — LMS3655-Q1 5.5A, 5V Synchronous, 400kHz, Step-Down Converter Evaluation Module

The LMS3655MQEVM evaluation module (EVM) demonstrates the capabilities of the LMS3655-Q1 automotive integrated buck converter. For optimized EMI performance, the LMS3655-Q1 has Spread Spectrum built in and the  EVM has an EMI filter on the back side that assists with noise reduction. The (...)
User guide: PDF
Not available on TI.com
Evaluation board

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The LMS3655NQEVM evaluation module (EVM) demonstrates the capabilities of the LMS3655-Q1 automotive integrated buck converter. For optimized EMI performance, the LMS3655-Q1 has Spread Spectrum built in and the  EVM has an EMI filter on the back side that assists with noise reduction. The (...)
User guide: PDF
Not available on TI.com
Simulation model

LMS36553-Q1 PSpice Transient Model

SNAM217.ZIP (105 KB) - PSpice Model
Simulation model

LMS36553-Q1 Unencrypted PSpice Transient Model

SNAM218.ZIP (7 KB) - PSpice Model
Simulation model

LMS36555-Q1 PSpice Transient Model

SNAM213.ZIP (108 KB) - PSpice Model
Simulation model

LMS36555-Q1 Unencrypted PSpice Transient Model

SNAM214.ZIP (7 KB) - PSpice Model
Simulation model

LMS3655A-Q1 PSpice Transient Model

SNAM216.ZIP (157 KB) - PSpice Model
Simulation model

LMS3655A-Q1 Unencrypted PSpice Transient Model

SNAM215.ZIP (7 KB) - PSpice Model
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 (...)
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