Skip to main content
Datasheets.com
Reference DesignAnalog

MAXREFDES1172: 12V/1A Isolated No-Opto Flyback DC-DC Converter using MAX17690

A 12W isolated no-opto flyback converter using the MAX17690. It delivers 12V/1A from an 8V-28V input with 90% efficiency, eliminating optocouplers and auxiliary windings.

View reference design

Overview

This design document specifies the MAXREFDES1172, a miniature isolated flyback DC-DC converter based on the MAX17690 peak current-mode controller. The design achieves output voltage regulation by sensing the reflected voltage across the primary winding, eliminating the need for an optocoupler or auxiliary transformer winding. It operates from an 8V to 28V input range to provide a regulated 12V output at up to 1A with a peak efficiency of 90%. The documentation covers hardware specifications, the no-opto control algorithm, temperature compensation techniques for rectifying diodes, and protection features including hiccup-mode short-circuit and thermal shutdown.

Use Cases

  • Isolated industrial power supplies
  • Programmable Logic Controllers (PLC)
  • Industrial I/O modules
  • Medical equipment
  • Telecommunications equipment
  • Distributed power systems

Topics

MAX17690
MAXREFDES1172
flyback converter
isolated DC-DC
no-opto
primary-side sensing
voltage regulation
power supply
Analog Devices
Maxim Integrated

Referenced Parts

MAX17690

Maxim Integrated

The MAX17690 eliminates the need for an optocoupler or auxiliary transformer winding and achieves ±5% output voltage regulation

MAX17595

Maxim Integrated

traditional flyback converter (using the MAX17595), shown in Figure 2.

SBR8U60P5

Diodes Incorporated

Allowing for reasonable design margin, the Diodes Incorporated SBR8U60P5 was chosen for this design

MAXREFDES1172: 12V/1A Isolated No-Opto Flyback DC-DC Converter using MAX17690 | Design Resources