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Why does the 75/300 have VCC at 3.4V?

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TechAUmNu
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Why does the 75/300 have VCC at 3.4V?

Is there any reason why the 75/300 has its VCC set to 3.4V?

yoyoJosh
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I have the same question. From the MCP16311 datasheet, it looks like VCC is set for 3.44V.  

Is there a reason for this specific voltage, instead of say 3.3V?

TheFallen
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Judging by the +5V regulator next to it Vedder is using the same low side resistor (10kΩ) and is only using an E12/24 resistor pack so 33kΩ is close enough to +3V3. +4% error?
I guess it'll have a slight effect on any analogue read values but that's easily fixed in software.

It is odd that he's gone for a E96 resistor on the +5V high side but not done similarly for the +3V3 that would get you a 31.6kΩ which brings the output to +3.328V, a +0.8% error
Unfortunately as the hardware is a closed source project we can't apply any bug fixes.

TechAUmNu
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The config file specifies it as 3.4v so it doesn't make any difference other than being higher than other boards. Can't remember the max voltage on the stm32 power.