The iW1699 is a high-performance AC/DC controller designed to drive an external power N-channel MOSFET for peak current mode PWM flyback power supplies. It uses Renesas' PrimAccurate™ primary-side control technology, eliminating the need for a secondary-side regulator and optocoupler, reducing component count and solution cost while easily meeting the US DoE’s external power supply efficiency standard and the EU’s Code of Conduct, Version 5, Tier 2 external power supply standard, with no-load power consumption less than 30mW.

It integrates a constant current mode on some options so it can be used in adapter applications, with a constant current accuracy >3%. Additional features include Renesas' proprietary EZ-EMI™ technology, adaptive multi-mode PWM/PFM control for optimal efficiency across all loads, five selectable cable and connector voltage drop compensation voltages, and robust operation with full protection from overvoltage and over-temperature.

For lower output ripple, see the iW1699B 30W AC/DC off-line controller page.


  • Meets DoE external power supply regulation and EU CoC Version 5, Tier 2
    • Less than 30mW no-load power consumption
  • Active start-up - Reduces turn-on time without impacting no-load power consumption
  • Low 6µA start-up current
  • Selectable voltage offset compensation for voltage loss in cables and connectors (5 options)
    • Selectable via single resistor to ground
  • PrimAccurate™ - Primary-side control, no optocoupler needed
  • Intrinsically low noise solution - No audible noise over entire operating range
  • Adaptive multi-mode PWM/PFM control for optimal efficiency across load range
  • EZ-EMI™ design to easily meet global EMI specifications
  • Fast dynamic load regulation
  • Fully protected from fault conditions
    • Overvoltage/Over-temperature protection (latch option)
    • Output overvoltage and overcurrent
    • Input undervoltage protection
    • Sense-resistor short circuit protection




  • Power adapters for portable electronics
  • Consumer electronics power supplies
  • Linear AC/DC power supply replacement

Design & Development