Alternative Parts
Overview
Features and Benefits
- 4.5V to 100V Input Voltage Range
- Internal 420mA, 150V Power Switch
- Boundary Mode Operation
- No Transformer Third Winding or Opto-Isolator Required for Regulation
- Improved Primary-Side Winding Feedback Load Regulation
- VOUT Set with Two External Resistors
- BIAS Pin for Internal Bias Supply and Power Switch Driver
- No External Start-Up Resistor
- 16-Lead MSOP Package
Product Details
The LT3512 is a high voltage monolithic switching regulator specifically designed for the isolated flyback topology. No third winding or opto-isolator is required for regulation as the part senses output voltage directly from the primary-side flyback waveform. The device integrates a 420mA, 150V power switch, high voltage circuitry, and control into a high voltage 16-lead MSOP package with four leads removed.
The LT3512 operates from an input voltage range of 4.5V to 100V and delivers up to 4.5W of isolated output power. Two external resistors and the transformer turns ratio easily set the output voltage. Off-the-shelf transformers are available for several applications. The high level of integration and the use of boundary mode operation results in a simple, clean, tightly regulated application solution to the traditionally tough problem of isolated power delivery.
Applications
- Isolated Telecom Power Supplies
- Isolated Auxiliary/Housekeeping Power Supplies
- Isolated Industrial, Automotive and Medical Power Supplies
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Documentation
Reliability Data (1)
Evaluation Kit Manuals (1)
Tools & Simulations
LTspice
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.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.

Models for the following parts are available in LTspice:
Reference Materials
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.
PCN-PDN Information
Support & Discussions
LT3512 Discussions
Sample & Buy
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 Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.