1. Products
  2. Power Management
  3. Switching Regulators
  4. Step-Down (Buck) Regulators
  5. External Power Switch Buck Controllers
  6. LT3741


Overview

Features and Benefits

  • Control Pin Provides Accurate Control of Regulated Output Current
  • ±1.5% Voltage Regulation Accuracy
  • ±6% Current Regulation Accuracy
  • 6V to 36V Input Voltage Range
  • Wide Output Voltage Range Up to (VIN – 2V)
  • Average Current Mode Control
  • <1μA Shutdown Current
  • Up to 94% Efficiency
  • Additional Pin for Thermal Control of Load Current
  • Thermally Enhanced 4mm × 4mm QFN and 20-Pin FE Package

Product Details

The LT3741 and LT3741-1 are fixed frequency synchronous step-down DC/DC controllers designed to accurately regulate the output current at up to 20A. The average current-mode controller will maintain inductor current regulation over a wide output voltage range of 0V to (VIN – 2V). The regulated current is set by an analog voltage on the CTRL pins and an external sense resistor. Due to its unique topology, the LT3741 is capable of sourcing and sinking current. If sinking current is not required, or for parallel applications, use the LT3741-1. The regulated voltage and overvoltage protection are set with a voltage divider from the output to the FB pin. Soft-Start is provided to allow a gradual increase in the regulated current during startup. The switching frequency is programmable from 200kHz to 1MHz through an external resistor on the RT pin or through the use of the SYNC pin and an external clock signal.

Additional Features include an accurate external reference voltage for use with the CTRL pins, an accurate UVLO/EN pin that allows for programmable UVLO hysteresis, and thermal shutdown.

Applications

  • General Purpose Industrial
  • Super-Cap Charging
  • Applications Needing Extreme Short-Circuit Protection and/or Accurate Output Current Limit
  • Constant Current or Constant Voltage Source

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Evaluation Kits (1)

Tools & Simulations

LTspice

LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

To launch ready-to-run LTspice demonstration circuits for this part:

Step 1: Download and install LTspice on your computer.

Step 2: Click on the link in the section below to download a demonstration circuit.

Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.

LTspice

Models for the following parts are available in LTspice:

LT3741

Product Recommendations

LT3741 Companion Parts

Recommended Related Parts

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.

Part Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
LT3741EFE#PBF Material Declaration Reliability Data 20-Lead TSSOP w/ EP
LT3741EFE#TRPBF Material Declaration Reliability Data 20-Lead TSSOP w/ EP
LT3741EFE-1#PBF Material Declaration Reliability Data 20-Lead TSSOP w/ EP
LT3741EFE-1#TRPBF Material Declaration Reliability Data 20-Lead TSSOP w/ EP
LT3741EUF#PBF Material Declaration Reliability Data 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LT3741EUF#TRPBF Material Declaration Reliability Data 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LT3741EUF-1#PBF Material Declaration Reliability Data 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LT3741EUF-1#TRPBF Material Declaration Reliability Data 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LT3741IFE#PBF Material Declaration Reliability Data 20-Lead TSSOP w/ EP
LT3741IFE#TRPBF Material Declaration Reliability Data 20-Lead TSSOP w/ EP
LT3741IFE-1#PBF Material Declaration Reliability Data 20-Lead TSSOP w/ EP
LT3741IFE-1#TRPBF Material Declaration Reliability Data 20-Lead TSSOP w/ EP
LT3741IUF#PBF Material Declaration Reliability Data 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LT3741IUF#TRPBF Material Declaration Reliability Data 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LT3741IUF-1#PBF Material Declaration Reliability Data 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LT3741IUF-1#TRPBF Material Declaration Reliability Data 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
Wafer Fabrication Data R548 Reliability Data

PCN-PDN Information

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Sample & Buy


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List Pricing


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Evaluation Boards

Pricing displayed is based on 1-piece.

Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.

Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.