ADG3304 Blow Up

Have seen 2 failures of an ADG3304.  I need to try and get some insight of how this could be occurring.

Below is my schematic.  The ADG3304 is U27. 

In this design VCCA should always be less then VCCY.  The failure does not occur at power up.

Should the unused inputs (Y1 and Y2) be grounded?

And the failed part (U27).  Note the puncture in the component body:

  • 0
    •  Analog Employees 
    on Sep 18, 2020 3:39 AM

    Hi LiburdiEng,

    Can you tell me more details about the failures that you are encountering in ADG3304 i.e., shorted pins or any unwanted voltage levels? When does failure occur?

    For the unused input channels, you must tie it into a known logic level. In your case, you may tie it to the ground.

    Best regards,

  • As the chip manufacturer, I'm looking for you to describe for me some possible failure modes that could produce a catastrophic failure such as this.  

    I don't believe the failure occurred at any specific or meaningful point in time.  Even though I am using the OE pin, currently the ADC and level shifter are running continuously.

    I have no reason to believe a short circuit of any pins occured.  Measuring the failed part now with a meter, none of the input channel pins appear to be shorted to ground, either of the voltage rails or to each other.

    Could leaving the input channels unterminated produce a failure mode that could blow up the part like this?

  • 0
    •  Analog Employees 
    on Sep 22, 2020 12:51 AM in reply to LiburdiEng

    Hi LiburdiEng,

    Can you tell us additional information so we can help you further?

     - How many boards have you tested that show similar failure?
     - Can you tell us how many units have you observed failing?
     - What temperature range does your application run?
     - What is the power-up sequence of the board?

    Also, we would suggest going back to your point of purchase as they can help support and redirect product failure concerns, in your case, "blowing-up". Note that ADI only provides warranty coverage or any quality, reliability, failure analysis, applications, and other support on products purchased through ADI authorized distributors and sales offices. To ensure you are receiving unused, legitimate ADI products, please ensure all purchases are made through ADI authorized distributors and sales offices listed on our website at Sales and Distribution | Analog Devices.
    You can get more information on this topic on our website at Quality and Reliability Programs | Analog Devices.