MAXREFDES1163: ±15V/100mA or ±12V/50mA output, ISO-BUCK DC-DC power module

The MAXREFDES1163 is a high-efficiency, iso-buck DC-DC power module based on the MAX17681. It accepts an input voltage range from 17V to 32V and adjusts the output voltage through primary-side feedback. The reference design provides two output configurations: In one configuration, the output is set to ±15V @ 100mA with ±10% regulation accuracy; in the second configuration, a post-regulator (MAX17651) is used to produce a ±12V @ 50mA output. The output voltage regulation accuracy is within ±3%. This iso-buck isolated power module is available in the MAX17681 in a 10-pin (3mm x 2mm) TDFN package and the MAX17651 in a 6-pin TSOT package. The MAXREFDES1163's pin pitch complies with the Distributed Power Source Open Standards Alliance's (DOSA) open standard for DC/DC module power supplies. Two transformer options are provided, one is from Wurth; the other is from Chinese transformer manufacturer HanRun, which is convenient for users to choose. The reference design provides 1500V electrical isolation.

Key Features

• ±15V@100mA or ±12V@50mA output

• 17V to 32V input voltage range

• EN/UVLO input

• 200kHz switching frequency

• 89% peak efficiency

• Overcurrent protection

• No optocoupler design

• Output power up to 3W

• Thermal Protection

• Proven PCB layout

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Design, build and test

This reference design introduces the MAXREFDES1163 hardware circuit design and provides detailed technical guidance for designing an iso-buck converter using Maxim's MAX17681A current-mode controller. The power supply has been built and tested.

design resources