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I'm trying to use a MAX541 DAC (datasheet here) with a Tiva LaunchPad (TM4C123G). I've gotten this to work with other DACs, the problem is that that those DACs required 3.3 volts and the MAX541 requires 5 volts.

The Tiva LaunchPad outputs 3.3V. I've purchased this RECOM ROE-3.305S DC/DC Converter which is supposed to convert 3.3V to 5V. However, when using it with the 3.3V input, it's outputting 6.35 volts and not the 5 volts that I need.

The DC/DC converter simply has four pins that plug into a breadboard: -Vin, +Vin, -Vout, +Vout. I simply plug the ground of the Tiva LaunchPad to the -Vin. The 3.3V power from the Tiva LaunchPad to the +Vin. Still I get 6.35V and not 5volts. Am I doing something wrong? Anyone?

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  • \$\begingroup\$ Can you share the schematics section including regulator. Capacitors and any other load connected? \$\endgroup\$ – Umar Jan 10 '17 at 4:50
  • \$\begingroup\$ Also, where do you measure 6.35V? \$\endgroup\$ – Vladimir Cravero Jan 10 '17 at 8:21
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I suspect that the DC/DC converter module requires a minimum load. Notice that the regulation is specified for 20% to 100% load. But the datasheet doesn't say what happens when load is less than 20%.

You can check this hypothesis, connect a 100Ω dummy load resistor (it should be rated for 0.25W or more), and measure the output voltage.

datasheet snippet (source: p.2 in the datasheet)

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