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ISO3082: iso RS485 Power consumption compare to discreet

Part Number: ISO3082

We must implement an isolated RS485 Half Duplex Interface with 2500V Isolation and a Slew-Rate limited Driver for 11500 Baud. So we found the IS3092 IC which combines a RS485 Transceiver and a galvanic isolation. The isolated Power for the Transsceiver is generated with an SN6501.

 

During calculation of power consumption (No Load) we run in a problem:

 iso 3086.docx

1. Datasheet page 11, Figure 5. ISO3082 Supply Current vs Data Rate With No Load

 

The Power Consumption at ICC2 of 25 mA@5V at 100 kBit is significant higher than an discrete Solution ISO7141+SN65HVD3082E (9+5=11 mA)

 

The faster part, for example ISO0386 (20 Mbaud) consumes only 11 mA at 1 MBaud.

 

@TI

  • Is this an failure in the datasheet?
  • What is the difference between the ISO3082 and the ISO7141+SN65HVD3082E?

REGARDS,

 

  • Hi Kamal Najmi,

    Thanks for bringing this question to us. I am surprised by this result as well. I am going to need some more time to check in to the difference between ISO3082 and ISO7141+SN65HVD3082E. Our expert on this device is currently out of office. I will respond by the close of business next Tuesday.

    Thank you for your understanding and patience,
    Dan
  • In reply to Dan Kisling:

    Hi Kamal Najmi,

    I apologize for the delay in response. I was not able to find an answer by today, but we are still looking. With the holidays approaching, many of our experts are out of office. These questions are very important to us, and we will continue to work to resolve this as quickly as possible. I will update you on our progress by Thursday, December 14.

    Thank you for your understanding and patience,
    Dan
  • In reply to Dan Kisling:

    Hi Kamal Najmi,

    Thank you for your patience. I have just discussed the ISO3082 power dissipation with relevant experts.

    The numbers listed in the datasheet are correct. The ISO3082 has an older technology isolator inside of it (from 2008). ISO7141 has newer isolator technology(2013) that is more efficient.

    Furthermore, the ISO774x has even newer isolator technology that is even lower power while also having higher isolation, stronger CMTI, wider supply range, and better immunity and robustness.

    Let me know if that answers your question.
    Best regards,
    Dan
  • In reply to Dan Kisling:

    There are plans to update the ISO3082 family or provide a new series of integrated RS485-Transceiver and Isolator?

  • In reply to Kamal Najmi:

    Hi Kamal Najmi,

    I have sent you an email regarding your question.
    If I have resolved your issue with understanding ISO3082 power consumption, please click "this resolved my issue." If you have further questions please either reply to this thread or start a new thread.
    Thanks again for your questions!

    Best regards,
    Dan

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