LT3741
LT3741-1
PRODUCTION
High Power, Constant Current, Constant Voltage, Step-Down Controller
- Part Models
- 16
- 1ku List Price
- Starting From $5.98
Overview
- 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
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
Documentation
Data Sheet 1
User Guide 1
Application Note 1
Technical Articles 1
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 Model | Pin/Package Drawing | Documentation | CAD Symbols, Footprints, and 3D Models |
|---|---|---|---|
| LT3741EFE#PBF | 20-Lead TSSOP w/ EP | ||
| LT3741EFE#TRPBF | 20-Lead TSSOP w/ EP | ||
| LT3741EFE-1#PBF | 20-Lead TSSOP w/ EP | ||
| LT3741EFE-1#TRPBF | 20-Lead TSSOP w/ EP | ||
| LT3741EUF#PBF | 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LT3741EUF#TRPBF | 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LT3741EUF-1#PBF | 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LT3741EUF-1#TRPBF | 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LT3741IFE#PBF | 20-Lead TSSOP w/ EP | ||
| LT3741IFE#TRPBF | 20-Lead TSSOP w/ EP | ||
| LT3741IFE-1#PBF | 20-Lead TSSOP w/ EP | ||
| LT3741IFE-1#TRPBF | 20-Lead TSSOP w/ EP | ||
| LT3741IUF#PBF | 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LT3741IUF#TRPBF | 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LT3741IUF-1#PBF | 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LT3741IUF-1#TRPBF | 20-Lead QFN (4mm x 4mm x 0.75mm w/ EP) |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
Apr 6, 2022 - 22_0068 Laser Top Mark for ETSSOP and TSSOP Packages Assembled in ADPG [PNG] and UTL |
||
| LT3741EFE#PBF | PRODUCTION | |
| LT3741EFE#TRPBF | PRODUCTION | |
| LT3741EFE-1#PBF | PRODUCTION | |
| LT3741EFE-1#TRPBF | PRODUCTION | |
| LT3741IFE#PBF | PRODUCTION | |
| LT3741IFE#TRPBF | PRODUCTION | |
| LT3741IFE-1#PBF | PRODUCTION | |
| LT3741IFE-1#TRPBF | PRODUCTION | |
|
May 18, 2026 - 26_0072 Epoxy Change for Select TSSOP Products |
||
| LT3741EFE-1#PBF | PRODUCTION | |
| LT3741EFE-1#TRPBF | PRODUCTION | |
| LT3741IFE-1#PBF | PRODUCTION | |
| LT3741IFE-1#TRPBF | PRODUCTION | |
|
Jan 20, 2022 - 21_0269 Addition of Alternate Assembly Site ASE Taiwan for Select LFCSP Products |
||
| LT3741EUF#PBF | PRODUCTION | |
| LT3741EUF#TRPBF | PRODUCTION | |
| LT3741EUF-1#PBF | PRODUCTION | |
| LT3741EUF-1#TRPBF | PRODUCTION | |
| LT3741IUF#PBF | PRODUCTION | |
| LT3741IUF#TRPBF | PRODUCTION | |
| LT3741IUF-1#PBF | PRODUCTION | |
| LT3741IUF-1#TRPBF | PRODUCTION | |
This is the most up-to-date revision of the Data Sheet.
Software Resources
Can't find the software or driver you need?
Request a Driver/SoftwareHardware Ecosystem
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| LTC3880 | RECOMMENDED FOR NEW DESIGNS | Dual Output PolyPhase Step-Down DC/DC Controller with Digital Power System Management |
Tools & Simulations
LTspice 3
- LT3741 Demo Circuit - High Power, CC, CV, Step-Down LED Controller (12V to Up to 6V LED @ 20A)
- LT3741 Demo Circuit - High Power, CC, CV, Step-Down Controller (30V to 20V @ 1.3A)
- LT3741 Demo Circuit - CC, CV, Super Capacitor Charger (12V to 5V @350mA)
Models for the following parts are available in LTspice:
- LT3741
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.
Evaluation Kits
LT3741EFE Demo Board | 120W LED Driver, 12V ≤ VIN ≤ 24V, CC/CV Synchronous Step-Down Controller, VOUT = 6V @ 20A