1. Products
  2. Power Management
  3. Switching Regulators
  4. Flyback, Forward, and Isolated Controller
  5. LTC3725

Alternative Parts


Features and Benefits

  • High Speed Gate Driver for Forward Converter
  • On-Chip Rectifier and Self-Starting Architecture Eliminates Need for Separate Gate Drive Bias Supply
  • Wide Input Voltage Supply Range: 9V and Up
  • Linear Regulator Controller for Fast Start-Up
  • Precision UVLO with Adjustable Hysteresis
  • Overcurrent Protection
  • Volt-Second Limit Prevents Transformer Core Saturation
  • Voltage Feedforward for Fast Transient Response
  • Available in 10-Lead MSOP Package

Product Details

The LTC3725 is a controller for a single-switch forward converter and includes an on-chip gate driver.

For secondary-side control, combine the LTC3725 with the LTC3706 PolyPhase® secondary-side synchronous forward controller to create a complete forward converter using a minimum of discrete parts. A proprietary scheme is used to multiplex gate drive signals across the isolation barrier through a tiny pulse transformer. The on-chip rectifier and the same pulse transformer provide gate drive bias power.

Alternatively, the LTC3725 can be used as a standalone voltage mode controller in a primary-side control architecture with optoisolator feedback. Voltage feedforward provides excellent line regulation and transient response.


  • Isolated 48V Telecommunication Systems
  • Internet Servers and Routers
  • Distributed Power Step-Down Converters
  • Automotive and Heavy Equipment

Product Lifecycle icon-not-recommended Not Recommended for New Designs

This designates products ADI does not recommend broadly for new designs.

Evaluation Kits (13)

Tools & Simulations


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.


Models for the following parts are available in LTspice:


Product Recommendations

LTC3725 Companion Parts

Recommended µModule Regulator

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
LTC3725EMSE#PBF Material Declaration Reliability Data 10-Lead MSOP w/ EP
LTC3725EMSE#TRPBF Material Declaration Reliability Data 10-Lead MSOP w/ EP
LTC3725IMSE#PBF Material Declaration Reliability Data 10-Lead MSOP w/ EP
LTC3725IMSE#TRPBF Material Declaration Reliability Data 10-Lead MSOP w/ EP
Wafer Fabrication Data R419 Reliability Data

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Sample & Buy

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Buy Now 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.