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I am feeding the I2C pins of a micro-controller into the converter shown in the circuit below to convert it to 1-wire protocol: However, the output will be at the level of 3.3 volts.

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I was considering the fact that with the voltage drop along the electric cable holding the Data_Sig Bus, we will lose data. Is it a better idea to convert it to 5v using this circuit:

enter image description here

I am confused about the following scenarios:

  1. Converting the two wires SDA and SCL seperately to 5 volts and then feeding them to the Single-Channel 1-Wire Master?
  2. Feedback the Vcc of 5 volts to the "Single-Channel 1-Wire Master" so the output will be one-wire at the level of 5 volts?
    1. Converting the Data_sig from 3,3 to 5 volts at the output?
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    \$\begingroup\$ It depends on the length and number of 1-Wire devices you need to support. Your schematic suggests you are using simple R passive pullup which would seem to indicate you have few and close devices. What makes you think you have a voltage drop issue to contend with? \$\endgroup\$
    – Jack Creasey
    Commented Jan 5, 2017 at 17:03
  • \$\begingroup\$ How far is the slave 1 wire device? If they are on the same PCB, or with in a module, still there shouldn't be any problems. 1 wire protocol is also built for communication with devices placed even tens of meters apart. Pull up needs to be shaped accordingly. \$\endgroup\$
    – User323693
    Commented Jan 6, 2017 at 0:51
  • \$\begingroup\$ @JackCreasey Yes, the maximum distance can be 10 meters between a device and a device,, this is why we think that we might have big voltage drop. I2C is good for short distances, but 1-Wire is for long distances. @ Umar 10m Max distance. It will be a cable not PCB based connection. \$\endgroup\$
    – Badreddine Zebbiche
    Commented Jan 6, 2017 at 10:23
  • \$\begingroup\$ @BadreddineZebbiche. I use this board to drive about 85 meters of telephone cable with multiple temperature sensors and only R pullup without any difficulty from a Raspberry Pi: abelectronics.co.uk/docs/stock/raspberrypi/1wirepi/… I doubt your voltage drop will be of any real concern below 100 meters (telephone cable is about 6 Ohm/10k ft). I wrote an article on 1-Wire: packtpub.com/books/content/raspberry-pi-and-1-wire which might help. \$\endgroup\$
    – Jack Creasey
    Commented Jan 6, 2017 at 17:12

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Answer by @Jack from the one of the comments: "@BadreddineZebbiche. I use this board to drive about 85 meters of telephone cable with multiple temperature sensors and only R pullup without any difficulty from a Raspberry Pi: abelectronics.co.uk/docs/stock/raspberrypi/1wirepi/… I doubt your voltage drop will be of any real concern below 100 meters (telephone cable is about 6 Ohm/10k ft). I wrote an article on 1-Wire: packtpub.com/books/content/raspberry-pi-and-1-wire which might help. –"

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