Texas Instruments

LMS3655 Synchronous Step-Down Converters

Texas Instruments' LMS3655 are 5.5 A, 36 V synchronous, 400 kHz, step-down converters

Image of Texas Instruments' LMS3655 Synchronous Step-Down ConvertersTexas Instruments' LMS3655 synchronous buck regulators are optimized for high performance applications, providing an adjustable output of 1 V to 15 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 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.

Features
  • 96% peak efficiency while converting 12 V to 5 V
  • Low EMI and switch noise
    • Minimized switch node ringing
    • Pseudo-random spread spectrum
  • 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

Applications

  • Noise-sensitive medical applications
  • Telecom
  • High performance industrial 
  • 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 (typ.)
  • 32 µA IQ_VIN: quiescent current at 3.3 VOUT and no load (typ.)
  • 5.5 A continuous load current
  • Adjustable output voltage (1 V to 15 V)
  • ±1.5% reference voltage tolerance
  • 4 mm x 5 mm, 0.5 mm pitch SON package

LMS3655 Synchronous Step-Down Converters

ImageManufacturer Part NumberDescriptionVoltage - Input (Min)Voltage - Output (Min/Fixed)Voltage - Output (Max)Available QuantityPriceView Details
IC REG BUCK ADJ 5.5A 22VQFNLMS3655MMRNLTIC REG BUCK ADJ 5.5A 22VQFN3.5V1V15V225 - Immediate$61.33View Details
IC REG BUCK 5V 5.5A 22VQFNLMS36555QRNLTQ1IC REG BUCK 5V 5.5A 22VQFN3.9V5V-1254 - Immediate$69.64View Details
IC REG BUCK ADJ 5.5A 22VQFNLMS3655MQRNLTQ1IC REG BUCK ADJ 5.5A 22VQFN3.9V1V15V1772 - Immediate$69.64View Details
IC REG BUCK ADJ 5.5A 22VQFNLMS3655AMRNLRIC REG BUCK ADJ 5.5A 22VQFN3.5V1V15V0 - Immediate$29.36View Details
IC REG BUCK ADJ 5.5A 22VQFNLMS3655MMRNLRIC REG BUCK ADJ 5.5A 22VQFN3.5V1V15V0 - Immediate$29.36View Details
IC REG BUCK 5V 5.5A 22VQFNLMS36555QRNLRQ1IC REG BUCK 5V 5.5A 22VQFN3.9V5V-0 - Immediate$34.54View Details
IC REG BUCK ADJ 5.5A 22VQFNLMS3655MQRNLRQ1IC REG BUCK ADJ 5.5A 22VQFN3.9V1V15V0 - Immediate$34.54View Details
IC REG BUCK ADJ 5.5A 22VQFNLMS3655AMRNLTIC REG BUCK ADJ 5.5A 22VQFN3.5V1V15V247 - Immediate$61.33View Details
IC REG BUCK 3.3V 5.5A 22VQFNLMS36553QRNLTQ1IC REG BUCK 3.3V 5.5A 22VQFN3.9V3.3V-0 - Immediate$61.33View Details
IC REG BUCK ADJ 5.5A 22VQFNLMS3655AQRNLTQ1IC REG BUCK ADJ 5.5A 22VQFN3.9V1V15V0 - Immediate$61.33View Details
IC REG BUCK 5V 5.5A 22VQFNLMS3655LQRNLTQ1IC REG BUCK 5V 5.5A 22VQFN3.9V5V-0 - Immediate$61.33View Details
IC REG BUCK 3.3V 5.5A 22VQFNLMS3655NQRNLTQ1IC REG BUCK 3.3V 5.5A 22VQFN3.9V3.3V-1215 - Immediate$69.64View Details

Evaluation Modules

ImageManufacturer Part NumberDescriptionAvailable QuantityPriceView Details
EVAL BOARD FOR LMS3655Q1LMS3655AQEVMEVAL BOARD FOR LMS3655Q12 - Immediate$977.96View Details
EVAL BOARD FOR LMS3655Q1LMS3655MQEVMEVAL BOARD FOR LMS3655Q12 - Immediate$977.96View Details
EVAL BOARD FOR LMS3655Q1LMS3655NQEVMEVAL BOARD FOR LMS3655Q11 - Immediate$814.97View Details
Published: 2018-01-29

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