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ISO7761-Q1: ISO7761FQDDWQ1

Part Number: ISO7761-Q1

Hello,

We are using ISO7761FQDWQ1 digital isolator in our design.

I want to confirm below point:

In the ISO7761FQDWQ1 IC,  5 channel are forward and 1 is reverse, Considering this case:

Vcci/Vcc1 is the input power supply for the five channel and output power supply for remaning one channel

Vcco/Vcc2 is the output power supply for 5 channel and input power supply is for one channel.

 

So if the Vcco supply is not present (The input supply for the sixth channel) then the output status of sixth channel should be “Default (LOW)” Please confirm on the same.

  • Hi Pankaj,

    Thank you for posting, and welcome to E2E! I appreciate the details and images you've already shared.

    Yes, ISO7761F devices have a default "LOW" output, so in the case power to Vcc2 (pin 16) is not present while Vcc1 (pin 1) is powered, the state of OUTF (pin 7) will be LOW, as covered in the orange section of the device function table shown below:



    I hope this answers your question.


    Thank you,
    Manuel Chavez

  • Thank you Manuel,

    Still i just want to confirm that in the table (Row highlighted by you) the case is given, if the primary supply down, however for the sixth channel in ISO7761F ic , Vcco will the the primary supply and if it's down and  if Vcc1 is prenet then the ouput of 7th pin will be low right?

    Regards,

    Pankaj kumar

  • Hi Pankaj,

    Vcc1 can be referred to as the primary power supply while Vcc2 can be referred to as the secondary power supply.

    Vcci denotes the respective power supply of the isolator where the channel input pin is. For the sixth channel (Channel F) of ISO7761F, Vcc1 = Vcco and Vcc2 = Vcci.

    For the other five channels, Channels A - E, Vcc1 = Vcci and Vcc2 = Vcco.


    Thank you,
    Manuel Chavez