LT1374 - 4.5A, 500kHz Step-Down Switching Regulator

Features

  • Constant 500kHz Switching Frequency
  • High Power 16-Pin TSSOP Package Available
  • Uses All Surface Mount Components
  • Inductor Size Reduced to 1.8µH
  • Saturating Switch Design: 0.07Ω
  • Effective Supply Current: 2.5mA
  • Shutdown Current: 20µA
  • Cycle-by-Cycle Current Limiting
  • Easily Synchronizable
Designed for Automotive and Transportation Applications
AEC-Q100 data available for specific packages


Typical Application

LT1374 Typical Application
LT1374 Typical Application

Description

The LT1374 is a 500kHz monolithic buck mode switching regulator. A 4.5A switch is included on the die along with all the necessary oscillator, control and logic circuitry. High switching frequency allows a considerable reduction in the size of external components. The topology is current mode for fast transient response and good loop stability. Both fixed output voltage and adjustable parts are available.

A special high speed bipolar process and new design techniques achieve high efficiency at high switching frequency. Efficiency is maintained over a wide output current range by using the output to bias the circuitry and by utilizing a supply boost capacitor to saturate the power switch.

The LT1374 is available in standard 7-pin DD, TO-220, fused lead SO-8 and 16-pin exposed pad TSSOP packages. Full cycle-by-cycle short-circuit protection and thermal shutdown are provided. Standard surface mount external parts may be used, including the inductor and capacitors. There is the optional function of shutdown or synchronization. A shutdown signal reduces supply current to 20µA. Synchronization allows an external logic level signal to increase the internal oscillator from 580kHz to 1MHz.

Protected by U.S. Patents, Including 6111439, 5668493, 5656965

Packaging

CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
Drawing
RoHS
LT1374CFE#PBF TSSOP-16 FE C 05-08-1663 (BB) Yes
LT1374CFE#TRPBF TSSOP-16 FE C 05-08-1663 (BB) Yes
LT1374CR-5#PBF DDPAK-7 R C 05-08-1462 Yes
LT1374CR-5#TRPBF DDPAK-7 R C 05-08-1462 Yes
LT1374CR-5SYNC#PBF DDPAK-7 R C 05-08-1462 Yes
LT1374CR-5Sync#TRPBF DDPAK-7 R C 05-08-1462 Yes
LT1374CR-SYNC#PBF DDPAK-7 R C 05-08-1462 Yes
LT1374CR-Sync#TRPBF DDPAK-7 R C 05-08-1462 Yes
LT1374CR#PBF DDPAK-7 R C 05-08-1462 Yes
LT1374CR#TRPBF DDPAK-7 R C 05-08-1462 Yes
LT1374CS8-5#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374CS8-5#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374CS8-5SYNC#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374CS8-5Sync#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374CS8-SYNC#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374CS8-Sync#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374CS8#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374CS8#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374CT7-5#PBF TO-220 T7 C 05-08-1422 (Standard) Yes
LT1374CT7#PBF TO-220 T7 C 05-08-1422 (Standard) Yes
LT1374HVCFE#PBF TSSOP-16 FE C 05-08-1663 (BB) Yes
LT1374HVCFE#TRPBF TSSOP-16 FE C 05-08-1663 (BB) Yes
LT1374HVCR#PBF DDPAK-7 R C 05-08-1462 Yes
LT1374HVCR#TRPBF DDPAK-7 R C 05-08-1462 Yes
LT1374HVCS8#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374HVCS8#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1374HVIFE#PBF TSSOP-16 FE I 05-08-1663 (BB) Yes
LT1374HVIFE#TRPBF TSSOP-16 FE I 05-08-1663 (BB) Yes
LT1374HVIR#PBF DDPAK-7 R I 05-08-1462 Yes
LT1374HVIR#TRPBF DDPAK-7 R I 05-08-1462 Yes
LT1374HVIS8#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1374HVIS8#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1374IFE#PBF TSSOP-16 FE I 05-08-1663 (BB) Yes
LT1374IFE#TRPBF TSSOP-16 FE I 05-08-1663 (BB) Yes
LT1374IR-5#PBF DDPAK-7 R I 05-08-1462 Yes
LT1374IR-5#TRPBF DDPAK-7 R I 05-08-1462 Yes
LT1374IR-5SYNC#PBF DDPAK-7 R I 05-08-1462 Yes
LT1374IR-SYNC#PBF DDPAK-7 R I 05-08-1462 Yes
LT1374IR#PBF DDPAK-7 R I 05-08-1462 Yes
LT1374IR#TRPBF DDPAK-7 R I 05-08-1462 Yes
LT1374IS8-5#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1374IS8-5#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1374IS8-5SYNC#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1374IS8-SYNC#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1374IS8#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1374IS8#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1374IT7-5#PBF TO-220 T7 I 05-08-1422 (Standard) Yes
LT1374IT7#PBF TO-220 T7 I 05-08-1422 (Standard) Yes


LT1374 Package Drawing
LT1374 Package Drawing
LT1374 Package Drawing
LT1374 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
(1-99)
Price
(1k)*
RoHS
LT1374CFE#PBF TSSOP-16 C $5.38 $4.55 Yes
LT1374CFE#TRPBF TSSOP-16 C $4.67 Yes
LT1374CR-5#PBF DDPAK-7 C $5.50 $4.70 Yes
LT1374CR-5#TRPBF DDPAK-7 C $4.82 Yes
LT1374CR-5SYNC#PBF DDPAK-7 C $5.50 $4.70 Yes
LT1374CR-5Sync#TRPBF DDPAK-7 C $4.82 Yes
LT1374CR-SYNC#PBF DDPAK-7 C $5.50 $4.70 Yes
LT1374CR-Sync#TRPBF DDPAK-7 C $4.82 Yes
LT1374CR#PBF DDPAK-7 C $5.50 $4.70 Yes
LT1374CR#TRPBF DDPAK-7 C $4.82 Yes
LT1374CS8-5#PBF SO-8 C $5.00 $4.40 Yes
LT1374CS8-5#TRPBF SO-8 C $4.46 Yes
LT1374CS8-5SYNC#PBF SO-8 C $5.00 $4.40 Yes
LT1374CS8-5Sync#TRPBF SO-8 C $4.46 Yes
LT1374CS8-SYNC#PBF SO-8 C $5.00 $4.40 Yes
LT1374CS8-Sync#TRPBF SO-8 C $4.46 Yes
LT1374CS8#PBF SO-8 C $5.00 $4.40 Yes
LT1374CS8#TRPBF SO-8 C $4.46 Yes
LT1374CT7-5#PBF TO-220 C $5.35 $4.60 Yes
LT1374CT7#PBF TO-220 C $5.35 $4.60 Yes
LT1374HVCFE#PBF TSSOP-16 C $5.92 $5.00 Yes
LT1374HVCFE#TRPBF TSSOP-16 C $5.12 Yes
LT1374HVCR#PBF DDPAK-7 C $6.15 $5.10 Yes
LT1374HVCR#TRPBF DDPAK-7 C $5.22 Yes
LT1374HVCS8#PBF SO-8 C $5.75 $4.85 Yes
LT1374HVCS8#TRPBF SO-8 C $4.91 Yes
LT1374HVIFE#PBF TSSOP-16 I $6.74 $5.70 Yes
LT1374HVIFE#TRPBF TSSOP-16 I $5.82 Yes
LT1374HVIR#PBF DDPAK-7 I $7.00 $5.90 Yes
LT1374HVIR#TRPBF DDPAK-7 I $6.02 Yes
LT1374HVIS8#PBF SO-8 I $6.60 $5.55 Yes
LT1374HVIS8#TRPBF SO-8 I $5.61 Yes
LT1374IFE#PBF TSSOP-16 I $6.15 $5.20 Yes
LT1374IFE#TRPBF TSSOP-16 I $5.32 Yes
LT1374IR-5#PBF DDPAK-7 I $6.30 $5.40 Yes
LT1374IR-5#TRPBF DDPAK-7 I $5.52 Yes
LT1374IR-5SYNC#PBF DDPAK-7 I $6.30 $5.40 Yes
LT1374IR-SYNC#PBF DDPAK-7 I $6.30 $5.40 Yes
LT1374IR#PBF DDPAK-7 I $6.30 $5.40 Yes
LT1374IR#TRPBF DDPAK-7 I $5.52 Yes
LT1374IS8-5#PBF SO-8 I $5.75 $5.05 Yes
LT1374IS8-5#TRPBF SO-8 I $5.11 Yes
LT1374IS8-5SYNC#PBF SO-8 I $5.75 $5.05 Yes
LT1374IS8-SYNC#PBF SO-8 I $5.75 $5.05 Yes
LT1374IS8#PBF SO-8 I $5.75 $5.05 Yes
LT1374IS8#TRPBF SO-8 I $5.11 Yes
LT1374IT7-5#PBF TO-220 I $6.15 $5.30 Yes
LT1374IT7#PBF TO-220 I $6.15 $5.30 Yes
Buy NowRequest Samples
* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC187A-A LT1374CR | 4.5A SWITCH, 500kHz STEP-DOWN REGULATOR, 5.5V to 25Vin, 3.3V or 5.0V @ 4A OUTPUT, DD PACKAGE $75.00
DC187A-B LT1374CR-SYNC | 4.5A SWITCH, 500kHz STEP-DOWN REGULATOR, 5.5V to 25Vin, 3.3V or 5.0V @ 4A OUTPUT, DD PACKAGE $75.00
DC188A-A LT1374CS8 | 4.5A SWITCH, 500kHz STEP-DOWN REGULATOR, 5.5V to 25Vin, 3.3V or 5.0V @ 4A OUTPUT, SO8 PACKAGE $75.00
DC188A-B LT1374CS8-SYNC | 4.5A SWITCH, 500kHz STEP-DOWN REGULATOR, 5.5V to 25Vin, 3.3V or 5.0V @ 4A OUTPUT, SO8 PACKAGE $75.00
DC474A LT1374CFE | 4A, 500KHz Step Down Switching Regulator, 5-25Vin up to 4A, Jmpr Selectable 3.3 or 5Vout $100.00
Buy Now
Click here to view our complete list of demo boards

Designed for Automotive and Transportation Applications

AEC-Q100 data is available for these specific part numbers. Please contact your local sales representative for more information regarding reliability reports or to inquire about parts that are not included. For more information, view our Automotive and Transportation page

Part Number Package Temp Price
(1-99)
Price
(1k)*
RoHS
LT1374HVIFE#PBF TSSOP-16 I $6.74 $5.70 Yes
LT1374HVIFE#TRPBF TSSOP-16 I $5.82 Yes
LT1374IFE#PBF TSSOP-16 I $6.15 $5.20 Yes
LT1374IFE#TRPBF TSSOP-16 I $5.32 Yes
Buy NowRequest Samples
* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Applications

  • Portable Computers
  • Battery-Powered Systems
  • Battery Chargers
  • Distributed Power

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Design Tools

LTspice

LTspice® software is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. Click here to download LTspice

To launch a ready to run LTspice demonstration circuit for this part:

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To explore other ready to run LTspice demonstration circuits, please visit our Demo Circuits Collection.

Models for the following parts are available in LTspice:
LT1374
LT1374-5
LT1374HV
LT1374HV-5

Technical Support