Differences between VDD_5V and SYS_5V

General Discussion
1

Hello,
I need to power two SN75174 and a SN75175, this chips need 5V on power pin, it is safe use the power presento in the pin SYS_5V of the BeagleBone Black board or is better use the VDD_5V pin?
What are the differences between the pins?

Thanks a lot

2

I have no idea what board you’re referring to, and I know I’m old fashioned,
but the first place I would have turned to is the Schematic…

(Ok ok, second pass reveals BBB, but you made me read; Tags people; Use them!)

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3

VDD_5V is connected to the barrel jack and will only be 5V if powering from that.

SYS_5V is an output from the PMIC. This should be 5V regardless of powering from USB or barrel jack. This is switched internally by the PMIC from either of the 5V inputs. There will be a limit on how much power you can draw from this (would need to check the datasheet for the PMIC) , but for a couple of ICs there should be no problem.

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