Analog Devices Inc./Maxim Integrated MAXREFDES114D#

Overview

MAXREFDES114D# 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 MAXREFDES114D# datasheet, MAXREFDES114D# pinout, MAXREFDES114D# application, or MAXREFDES114D# equivalent, this page provides verified board-level specifications, transformer vendor mapping (Halo HR051441), isolation architecture details, EMI-reduction features including frequency dithering, and validated transient/efficiency performance data across 17–36V input range.

Technical Context

The MAXREFDES114D# 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 functional insulation with 3000V optocoupler-based feedback for safety-critical industrial environments.

Key control functions include EN/UVLO (16.5V start), OVI protection (37.0V shutdown), soft-start, hiccup-mode overcurrent, soft-stop clamp capacitor discharge, and negative current limiting in the clamp switch path - all coordinated by the MAX17599 to ensure robust operation under brownout, overload, and thermal stress.

Key Specifications

Availability

MAXREFDES114D# 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 rapid prototyping support.

Supply support for MAXREFDES114D# 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 precision analog, mixed-signal, and power management ICs for industrial, automotive, and computing applications.

The MAXREFDES reference design series targets rapid validation of isolated power architectures - specifically enabling quick adoption of active-clamp forward converters in harsh industrial environments.

FAQ

What is the transformer used on the MAXREFDES114D# reference board?

The MAXREFDES114D# uses the Halo HR051441 transformer, selected for its compatibility with the active-clamp forward topology and optimized flux swing at 330kHz. This transformer enables functional isolation, supports the 17–36V input range, and contributes to the board's 92% peak efficiency. The MAXREFDES114D# design files specify exact winding ratios and leakage inductance matching required for stable operation with the MAX17599 controller.

Does MAXREFDES114D# support input undervoltage lockout and overvoltage protection?

Yes, the MAXREFDES114D# implements both EN/UVLO and OVI protection via the MAX17599 controller. The EN/UVLO threshold is set to 16.5V, ensuring reliable startup above brownout conditions, while OVI triggers shutdown at 37.0V to protect downstream circuitry. These thresholds are configured using resistor dividers R6, R7, and R11 on the MAXREFDES114D# board, and are fully documented in the reference design's hardware description.

How does the active-clamp reset topology improve performance on MAXREFDES114D#?

The active-clamp reset topology on MAXREFDES114D# reduces voltage stress on primary MOSFETs, allows larger transformer flux swing (enabling smaller magnetics), and eliminates dissipative snubber losses - directly contributing to its 92% peak efficiency and compact 20mm × 40mm footprint. It also enables zero-voltage switching via programmable dead time between NDRV and AUXDRV, lowering EMI and conduction losses compared to passive reset methods.

Can MAXREFDES114D# be used for EMI-sensitive applications?

Yes, the MAXREFDES114D# supports low-EMI operation through programmable frequency dithering, which spreads spectral energy across a band around 330kHz. This feature is implemented via the MAX17599's internal dithering circuitry and requires no external components. Measured output ripple at 2A load and transient response waveforms confirm suitability for noise-sensitive industrial communication interfaces and precision analog signal chains.

What protection features are integrated into MAXREFDES114D#?

The MAXREFDES114D# integrates hiccup-mode overcurrent protection, thermal shutdown, soft-start, soft-stop clamp capacitor discharge, and negative current limiting in the clamp switch path - all managed by the MAX17599 controller. These protections ensure safe restart after faults, controlled turn-off during shutdown, and sustained operation under adverse industrial conditions such as voltage surges, load transients, and ambient temperature extremes.