LT1375 - 1.5A, 500kHz Step-Down Switching Regulators


  • Constant 500kHz Switching Frequency
  • Easily Synchronizable
  • Uses All Surface Mount Components
  • Inductor Size Reduced to 5µH
  • Saturating Switch Design: 0.4 ohms
  • Effective Supply Current: 2.5mA
  • Shutdown Current: 20µA
  • Cycle-by-Cycle Current Limiting

Typical Application

LT1375 Typical Application
LT1375 Typical Application


The LT1375/LT1376 are 500kHz monolithic buck mode switching regulators. A 1.5A 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. A shutdown signal will reduce supply current to 20µA on both parts. The LT1375 can be externally synchronized from 580kHz to 900kHz with logic level inputs.

The LT1375/LT1376 fit into standard 8-pin PDIP and SO packages, as well as a fused lead 16-pin SO with much lower thermal resistance. Full cycle-by-cycle short-circuit protection and thermal shutdown are provided. Standard surface mount external parts are used, including the inductor and capacitors.

For low input voltage applications with 3.3V output, see LT1507. This is a functionally identical part that can operate with input voltages between 4.5V and 12V.


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
LT1375CN8-5#PBF N-8 N C 05-08-1510 (N8) Yes
LT1375CN8#PBF N-8 N C 05-08-1510 (N8) Yes
LT1375CS8-5#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1375CS8-5#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1375CS8#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1375CS8#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1375HVCS8#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1375HVCS8#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1375HVIS8#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1375HVIS8#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1375IN8-5#PBF N-8 N I 05-08-1510 (N8) Yes
LT1375IN8#PBF N-8 N I 05-08-1510 (N8) Yes
LT1375IS8-5#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1375IS8-5#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1375IS8#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1375IS8#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes

LT1375 Package Drawing
LT1375 Package Drawing
LT1375 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
LT1375CN8-5#PBF N-8 C $4.33 $3.50 Yes
LT1375CN8#PBF N-8 C $4.33 $3.50 Yes
LT1375CS8-5#PBF SO-8 C $4.50 $3.65 Yes
LT1375CS8-5#TRPBF SO-8 C $3.71 Yes
LT1375CS8#PBF SO-8 C $3.80 $3.20 Yes
LT1375CS8#TRPBF SO-8 C $3.26 Yes
LT1375HVCS8#PBF SO-8 C $4.20 $3.50 Yes
LT1375HVCS8#TRPBF SO-8 C $3.56 Yes
LT1375HVIS8#PBF SO-8 I $5.05 $4.24 Yes
LT1375HVIS8#TRPBF SO-8 I $4.31 Yes
LT1375IN8-5#PBF N-8 I $5.25 $4.20 Yes
LT1375IN8#PBF N-8 I $5.25 $4.20 Yes
LT1375IS8-5#PBF SO-8 I $5.40 $4.35 Yes
LT1375IS8-5#TRPBF SO-8 I $4.41 Yes
LT1375IS8#PBF SO-8 I $4.55 $3.85 Yes
LT1375IS8#TRPBF SO-8 I $3.91 Yes
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* 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
DC084B-B LT1375CS8-5 | FIXED 5V BUCK CONVERTER Contact Factory
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