• State TI Thinks Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 3 answers
  • Subscribers 13 subscribers
  • Views 1957 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Arduino input pins isolation

Luis Alberto Salazar Salazar
Prodigy 50 points
Other Parts Discussed in Thread: ISO7340C, ISO7341C, ISO7342C, ISO7740, ISO7742, ISO7741

Hello there, im working with an arduino board to get a power consumption recorder, i have the code ready but now i want to know what alternatives do i have to isolate the discrete signal on the input pines of the board, i like to know alternatives for control signal of 12, 24 and 110v. the number of signals are 4.

Best Regards

Luis Salazar

  • 0
    TI__Guru 55795 points
    Hi Luis,

    Could you please tell me if these discrete signals are at CMOS level (5V or 3.3V)?
    How many channels do you want to isolate?
    Are these independent I/O signals or is this a specific interface like I2C, SPI, RS-485?

    Regards,
    Koteshwar Rao
  • 0 in reply to Koteshwar Rao
    Prodigy 50 points

    Hello Koteshwar

    The project itself is based in an arduino board, the signals (4 in total) could be taken from the outlet signal of a plc, im not sure yet, thats why i like to know aletrnatives for 12, 24vdc and 110vac, the input pins of the board can manage only 5v max.

    Best.

    Luis Salazar

  • 0 in reply to Luis Alberto Salazar Salazar
    TI__Guru 55795 points
    Hello Luis,

    Currently we only have devices that can accept 5V or lower on both sides of device. If you know the high voltage are going to be well regulated then you could probably choose divide high voltage by a resistor divider to lower voltages than 5V and then pass them through isolator. Let me know if that is fine.

    Regards,
    Koteshwar Rao
  • 0 in reply to Koteshwar Rao
    Prodigy 50 points
    Hello, first i need to check the kind of signal, about the solution, i don't see too much problem in add some extra components, if i decide this solution can you help me with the selection of the necesary resistor divider? if the total of signals is 4 and the voltages are in 5vcd which component could be a good solution?

    Regards
    Luis Salazar
  • 0 in reply to Luis Alberto Salazar Salazar
    TI__Guru 55795 points
    Hi Luis,

    You can choose resistor values based on the available voltage that you want to down convert to 5V/3.3V. If basic isolation is sufficient, you could use ISO7340C. Based on flow directions of signals, any of ISO7340C, ISO7341C, ISO7342C should be suitable for you.
    For reinforced isolation (double of basic isolation), you could look at ISO7740, ISO7741, ISO7742.

    Regards,
    Koteshwar Rao