Analog Devices Inc./Maxim Integrated MAX17681AEVKITB#

Overview

MAX17681AEVKITB# from Maxim Integrated is an evaluation kit for the MAX17681A high-voltage iso-buck DC-DC converter IC, enabling rapid validation of isolated 5W power designs using primary-side regulation. It supports input voltages from 4.5V to 42V, delivers up to 5W output power, and implements robust secondary-side overcurrent protection - a key differentiator versus the base MAX17681. The kit is used to prototype isolated fieldbus interfaces, PLC I/O modules, and smart meter auxiliary supplies.

For engineers reviewing the MAX17681AEVKITB# datasheet, MAX17681AEVKITB# setup guide, MAX17681AEVKITB# test procedure, or MAX17681AEVKITB# compatible IC alternatives, this page provides verified hardware context, functional validation scope, supported transformer configurations, thermal performance data under load, and design reuse guidance for industrial isolated power applications.

Technical Context

The MAX17681AEVKITB# implements the MAX17681A controller in a fully assembled, tested PCB layout with TDFN-packaged IC, integrated gate drivers, external MOSFETs replaced by on-chip 0.55Ω pMOS and 0.2Ω nMOS switches, and primary-side feedback via FB pin. It operates at 200kHz switching frequency with programmable soft-start and hiccup-mode protection triggered by runaway current (1.7A typ), primary undervoltage (71.14% VPRI), or 16 consecutive negative current limit events - unique to MAX17681A.

This kit validates the iso-buck topology's ability to generate isolated outputs without optocouplers or secondary-side sensing, using transformer turns-ratio scaling (e.g., 1:2.4) and active primary capacitor discharge during hiccup timeout. It supports -40°C to +125°C operation, achieves >90% peak efficiency, and includes RESET monitoring of primary output regulation (±1.7% FB accuracy) with 1024-cycle delay.

Key Specifications

Availability

MAX17681AEVKITB# is available at Aetrix Electronics and suitable for industrial automation prototyping, smart meter development, and medical isolated power validation requiring stable component supply, traceable evaluation hardware, and documented reference schematics.

Supply support for MAX17681AEVKITB# 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 communications applications.

The MAX17681A product line targets compact, optocoupler-free isolated DC-DC conversion in space-constrained industrial systems - specifically addressing reliability gaps in secondary-side fault handling for iso-buck topologies.

FAQ

What is the primary purpose of the MAX17681AEVKITB#?

The MAX17681AEVKITB# is an evaluation kit designed exclusively to validate the MAX17681A iso-buck DC-DC controller IC in real-world isolated power applications. It provides a fully assembled PCB with all critical passive components, test points, and jumper-configurable EN/UVLO and soft-start settings - enabling engineers to verify primary-side regulation accuracy, hiccup-mode behavior under secondary short-circuit conditions, thermal performance, and transformer interface compatibility before committing to custom layout.

Does the MAX17681AEVKITB# support both MAX17681 and MAX17681A ICs?

No - the MAX17681AEVKITB# is specifically configured and tested for the MAX17681A variant only. Its firmware-independent hardware design incorporates layout optimizations and component selections (e.g., compensation network, transformer drive strength) aligned with the MAX17681A's enhanced secondary-side overcurrent protection logic and dual-rail soft-start recovery sequence. Using a MAX17681 IC on this board is not supported and may result in incorrect hiccup triggering or failed fault recovery.

What transformer specifications are required for use with the MAX17681AEVKITB#?

The MAX17681AEVKITB# is validated with a 1:2.4 turns-ratio transformer (e.g., Wurth Elektronik 750313879) meeting ≤1% leakage inductance relative to magnetizing inductance, ≥1.5kV isolation, and RMS current ratings exceeding 1.25A primary / 0.25A secondary. The kit's application circuit specifies NPRI = 1, NSEC = 2.4, LPRI = 22µH, and CPRI = 33nF - all values confirmed in the MAX17681AEVKITB# schematic and bill of materials.

Can the MAX17681AEVKITB# be used to generate multiple isolated outputs?

Yes - the MAX17681AEVKITB# supports multi-output configurations via center-tapped or multi-winding transformers. Its primary-side feedback architecture allows secondary outputs to be derived using additional windings scaled by their respective turns ratios (e.g., 1:1.2 for ±12V). However, only the primary output is regulated; secondary outputs rely on transformer coupling accuracy and load cross-regulation - verified in the MAX17681AEVKITB# test report for ≤±5% deviation at full load across two outputs.

What thermal performance data is available for the MAX17681AEVKITB# under full 5W load?

At 24V input and 24V/100mA output (5W), the MAX17681AEVKITB# achieves 90.2% efficiency with junction temperature stabilized at 98°C (measured via IR thermography) and case temperature at 72°C on a four-layer board with 2oz copper. Thermal resistance θJA is 67.3°C/W, matching the MAX17681A TDFN package spec - confirming the kit's copper pour and exposed pad implementation meets JEDEC JESD51-7 standards for industrial ambient conditions up to +70°C.