LT3641
PRODUCTIONDual Monolithic Buck Regulator with Power-On Reset and Watchdog Timer
- Part Models
- 10
- 1ku List Price
- Starting From $5.54
Overview
- High Voltage Buck Regulator:
- 4V to 42V Operating Range
- 1.3A Output Current
- Input Transient Protection to 55V
- Low Voltage Synchronous Buck Regulator:
- 2.5V to 5.5V Input Voltage Range
- 1.1A Output Current
- Synchronizable, Adjustable 350kHz to 2.5MHz Switching Frequency
- Programmable Power-On Reset Timer
- Programmable Window Mode Watchdog Timer
- Typical Quiescent Current: 290μA
- Short-Circuit Robust
- Programmable Soft-Start
- Low Shutdown Current: IQ < 1μA
- Thermal Shutdown
- Available in Thermally Enhanced 28-Lead (4mm × 5mm) QFN and 28-Lead TSSOP Packages
The LT3641 is a dual channel, current mode monolithic buck switching regulator with a power-on reset and a watchdog timer. Both regulators are synchronized to a single oscillator with an adjustable frequency (350kHz to 2.5MHz). At light loads, both regulators operate in low ripple Burst Mode® to maintain high effi ciency and low output ripple.
The high voltage channel is a nonsynchronous buck with an internal 2.4A top switch that operates from an input of 4V to 42V and input transient protection to 55V. The low voltage channel operates from an input of 2.5V to 5.5V. Internal synchronous power switches provide high effi ciency without the need of external Schottky diode. Both channels have cycle-by-cycle current limit, providing protection against shorted outputs.
The power-on reset and watchdog timeout periods are both adjustable using external capacitors. The window mode watchdog timer fl ags when the μP pulses group too close together or too far apart.
The LT3641 is available in a 28-pin 4mm × 5mm QFN package and 28-pin TSSOP package. Both packages have an exposed pad for low thermal resistance.
Applications
- Industrial Power Supplies
- Automotive Electronic Control Units
Documentation
Data Sheet 1
User Guide 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 |
|---|---|---|---|
| LT3641EFE#PBF | 28-Lead TSSOP w/ EP | ||
| LT3641EFE#TRPBF | 28-Lead TSSOP w/ EP | ||
| LT3641EUFD#PBF | 28-Lead QFN (4mm x 5mm x 0.75mm w/ EP) | ||
| LT3641EUFD#TRPBF | 28-Lead QFN (4mm x 5mm x 0.75mm w/ EP) | ||
| LT3641HFE#PBF | 28-Lead TSSOP w/ EP | ||
| LT3641HFE#TRPBF | 28-Lead TSSOP w/ EP | ||
| LT3641IFE#PBF | 28-Lead TSSOP w/ EP | ||
| LT3641IFE#TRPBF | 28-Lead TSSOP w/ EP | ||
| LT3641IUFD#PBF | 28-Lead QFN (4mm x 5mm x 0.75mm w/ EP) | ||
| LT3641IUFD#TRPBF | 28-Lead QFN (4mm x 5mm x 0.75mm w/ EP) |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
May 18, 2026 - 26_0072 Epoxy Change for Select TSSOP Products |
||
| LT3641EFE#PBF | PRODUCTION | |
| LT3641EFE#TRPBF | PRODUCTION | |
| LT3641HFE#PBF | PRODUCTION | |
| LT3641HFE#TRPBF | PRODUCTION | |
| LT3641IFE#PBF | PRODUCTION | |
| LT3641IFE#TRPBF | PRODUCTION | |
|
Apr 6, 2022 - 22_0068 Laser Top Mark for ETSSOP and TSSOP Packages Assembled in ADPG [PNG] and UTL |
||
| LT3641EFE#PBF | PRODUCTION | |
| LT3641EFE#TRPBF | PRODUCTION | |
| LT3641HFE#PBF | PRODUCTION | |
| LT3641HFE#TRPBF | PRODUCTION | |
| LT3641IFE#PBF | PRODUCTION | |
| LT3641IFE#TRPBF | PRODUCTION | |
|
Feb 20, 2022 - 21_0269 Addition of Alternate Assembly Site ASE Taiwan for Select LFCSP Products |
||
| LT3641EUFD#PBF | PRODUCTION | |
| LT3641EUFD#TRPBF | PRODUCTION | |
| LT3641IUFD#PBF | PRODUCTION | |
| LT3641IUFD#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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Tools & Simulations
LTspice 1
Models for the following parts are available in LTspice:
- LT3641
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
LT3641EFE Demo Board | Power-On Reset and Watchdog Timer, 7V ≤ VIN ≤ 42V (55V Transients), VOUT1 = 5V @ 1A, VOUT2 = 1.8V @ 0.8A
Resources
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