Hi, I'm trying to isolate I2C data lines and DC power for a sensor, does this look correct?
I'm using the RFM-0505S to isolate DC, it's $3 cheaper for a 5v vs 3.3v so I added a regulator after it to get my 3.3v.
https://www.mouser.ca/datasheet/2/468/RFM-1710978.pdf
Then I have the ISO1540DR isolating the SCL/SDA lines. Is it correct to have both GND1/GND2 and VCC1/VCC2 come from the isolated side? I can't see a problem with it but datasheet with it's example it shows otherwise. I don't have non isolated 3.3v and it doesn't feel right to put non isolated GND there.
https://datasheet.lcsc.com/szlcsc/1811082013_Texas-Instruments-ISO1540DR_C179739.pdf
One other thing, in the AZ1117 regulator datasheet it says if a .1uf capacitor runs in parallel of the output it needs to be 5mm away. My board is small so it will be closer, can I run about 6mm of trace in a loop?
The I2C lines do have resistors on each side just not in the image.
Thanks
I'm using the RFM-0505S to isolate DC, it's $3 cheaper for a 5v vs 3.3v so I added a regulator after it to get my 3.3v.
https://www.mouser.ca/datasheet/2/468/RFM-1710978.pdf
Then I have the ISO1540DR isolating the SCL/SDA lines. Is it correct to have both GND1/GND2 and VCC1/VCC2 come from the isolated side? I can't see a problem with it but datasheet with it's example it shows otherwise. I don't have non isolated 3.3v and it doesn't feel right to put non isolated GND there.
https://datasheet.lcsc.com/szlcsc/1811082013_Texas-Instruments-ISO1540DR_C179739.pdf
One other thing, in the AZ1117 regulator datasheet it says if a .1uf capacitor runs in parallel of the output it needs to be 5mm away. My board is small so it will be closer, can I run about 6mm of trace in a loop?
The I2C lines do have resistors on each side just not in the image.
Thanks
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