I am evaluating the Sparkfun DMX LED board schematics and I believe I see an issue. The U6 DC to DC isolated supply puts out 5V for VCC-ISO. U1, the MAX3485CSA/SP3485C RS485 transceiver datasheets says its VCC should be 3.3V. The schematics show the VCC-ISO 5V is connected to U1 VCC input. This would mean the part is being overdriven. I checked the two boards that I just purchased and confirmed there is 5V across pins 5 and 8 of U1. Is this an intentional override of the part? My boards have an SP3485C installed in U1 and they appear to work but they are putting out 5V on RO instead of 3.3V because of the high VCC. I would rather not rely on overdriven parts. A 3.3V LDO after the VCC-ISO could be used to create a 3.3V isolated supply for this chip. Another note is none of the parts on my board have silkscreen part designators.
Go ahead and file this as an ‘issue’ on the github to alert the engineering team and perhaps get some answers 
Thanks @TS-Russell, I did. Does someone actually monitor this github project? Another question from four months ago has not been replied to.
A lot ‘why’ for design decisions go to the nether realm (sometimes it’s not the original engineer and don’t know, sometimes it’s dictated by management, etc)…folks get busy and forget to circle back sometimes
Yours is a more pressing issue concerning a potential flaw, much more likely to see some action