Analog Devices Inc./Maxim Integrated MAXREFDES114B#

Overview

MAXREFDES114B# from Maxim Integrated is an isolated 24V-to-5V, 10W (2A) industrial reference design board implementing an active-clamp forward converter topology with the MAX17599 PWM controller. It delivers 92% peak efficiency at 24V input, features functional insulation, 330kHz switching, and compact 20mm × 40mm PCB layout optimized for PLC and sensor power rails.

For engineers reviewing the MAXREFDES114B# datasheet, MAXREFDES114B# pinout, MAXREFDES114B# application, or MAXREFDES114B# equivalent, key selection criteria include input voltage range (17–36V), output regulation accuracy (5V ±0.25V), hiccup-mode overcurrent protection, soft-start/soft-stop control, and transformer vendor-specific isolation compliance (Sumida 13324-T115).

Technical Context

The MAXREFDES114B# implements a wide-input (17V–36V), isolated forward-converter architecture using the MAX17599 active-clamp current-mode PWM controller. It employs zero-voltage switching via programmable dead time between NDRV and AUXDRV outputs, and uses a Sumida 13324-T115 transformer for reinforced isolation and flux-swing optimization.

Protection functions include EN/UVLO (16.5V turn-on), OVI (37.0V shutdown), thermal shutdown, negative current limiting in clamp sensing, and hiccup-mode overcurrent response. The feedback loop uses TLV431B + optocoupler for precise 5V regulation under line/load transients.

Key Specifications

Availability

MAXREFDES114B# is available at Aetrix Electronics and suitable for programmable logic controllers (PLCs), industrial process control systems, and isolated sensor interface modules requiring stable component supply and verified transformer-sourced isolation.

Supply support for MAXREFDES114B# includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) designs high-performance analog, mixed-signal, and power-management ICs for industrial, automotive, and communications applications.

The MAXREFDES reference design series targets rapid prototyping of robust, certified-isolation power supplies for harsh industrial environments - specifically enabling drop-in evaluation of active-clamp forward converters with pre-validated magnetics and safety margins.

FAQ

What is the primary function of the MAXREFDES114B# reference design?

The MAXREFDES114B# is a fully assembled, tested reference board that implements an isolated 24V-to-5V, 10W active-clamp forward converter. Its primary function is to provide engineers with a validated, transformer-sourced (Sumida 13324-T115), safety-compliant power solution for industrial control applications - eliminating the need to develop isolation power stages from scratch. The MAXREFDES114B# integrates the MAX17599 controller, synchronous rectification, and full protection circuitry on a 20mm × 40mm PCB.

Which transformer is used in the MAXREFDES114B# and why is it critical?

The MAXREFDES114B# uses the Sumida 13324-T115 transformer, selected for its reinforced insulation, optimized turns ratio, and compatibility with the MAX17599's active-clamp reset timing. This transformer ensures functional isolation per IEC 60950-1, enables efficient flux swing utilization, and maintains consistent regulation across the 17–36V input range. Using the specified Sumida part is essential to replicate the published 92% efficiency and transient performance of the MAXREFDES114B#.

Does the MAXREFDES114B# support input undervoltage and overvoltage protection?

Yes, the MAXREFDES114B# implements both input undervoltage lockout (UVLO) and overvoltage input (OVI) protection via the MAX17599's EN/UVLO and OVI pins. UVLO is set to 16.5V turn-on (with 1.21V internal threshold), ensuring reliable startup above brownout conditions. OVI triggers shutdown at 37.0V, protecting downstream circuitry. These thresholds are fixed by resistor dividers R6/R7/R11 on the MAXREFDES114B# board and are verified across temperature and load.

How does the MAXREFDES114B# achieve high efficiency and low EMI?

The MAXREFDES114B# achieves 92% peak efficiency by eliminating lossy snubbers through active-clamp reset, reducing switch voltage stress, and enabling zero-voltage switching via programmable dead time. For EMI reduction, it supports frequency dithering - spreading the 330kHz fundamental across a narrow band to lower peak emissions. Layout optimizations, including tight power loops and controlled trace impedance, further suppress conducted and radiated noise without external filters.

Can the MAXREFDES114B# be used directly in production, or is it evaluation-only?

The MAXREFDES114B# is designed for both evaluation and production use. It is fully assembled, tested, and qualified for industrial environments - featuring through-hole connectors for mechanical robustness, hiccup-mode fault protection, thermal shutdown, and functional insulation. While intended as a reference, its validated BOM, Gerber files, and performance data (including 5V ±0.25V regulation and 92% efficiency) support direct integration into volume-manufactured systems where Sumida 13324-T115 transformer sourcing is secured.