Off-line all-primary-sensing switching regulator

The ALTAIR04-900 is a high voltage all-primary-sensing switcher, operating directly from the rectified mains with minimum external parts. It combines a high-performance low voltage PWM controller chip and a 900 V avalanche-rugged power section in the same package.

Key Features

  • Optoless primary side constant voltage operations
  • Adjustable and mains-independent maximum output current for safe operations during overload/short-circuit conditions
  • 900 V avalanche-rugged internal power section
  • Quasi-resonant valley switching operation
  • Low standby consumption
  • Overcurrent protection against transformer saturation and secondary diode short-circuit
  • SO16N package

Circuit Diagram

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Technical Documentation

Product Specifications
Description Version Size
DS7028 DS7028: Off-line all-primary-sensing switching regulator 3.0 535 KB
Application Notes
Description Version Size
AN4154 AN4154: Power supply for energy meter and power line modem 3.0 1 MB
AN3290 AN3290: Reference design for double output SMPS for power line modem applications using ALTAIR04-900 primary controller 1.0 3 MB

HW Model & CAD Libraries

HW Model & CAD Libraries
Description Version Size
altair04-900 spice models 31 KB

Publications and Collaterals

Description Version Size
Brochure Power management guide 05.2016 4 MB

Tools and Software

Evaluation Tools
Solution Evaluation Tools
eDesignSuite Support & Community

Sample & Buy

Part Number Package Packing Type Marketing Status Unit Price (US$) * Quantity RDS(on) (Ω) (max) Transistor Breakdown Voltage (V) (min) Drain Current (A) (nom) ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors
ALTAIR04-900TR SO-16 Tape And Reel Active - - - - 0.7 NEC EAR99 - MORE INFO Get Sample Add to cart DISTRIBUTOR AVAILABILITY

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors

Quality & Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
ALTAIR04-900 ActiveSO-16IndustrialEcopack2
ALTAIR04-900TR ActiveSO-16IndustrialEcopack2

(**) The Material Declaration forms available on may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.