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ISO7641FC: Life Expectancy vs Working Voltage

Guru 16855 points

Part Number: ISO7641FC

Hi,

I would like to know Life Expectancy vs Working Voltage of ISO7641 as below(ISO7420FD datahseet), however it is nothing on the datasheet.

Could you share it if you have the data?

Best Regards,

Kuramochi

  • Hi TQ,

    Thanks for using our forums.

    We can look into this one. Is there a specific working voltage you are looking to use in the end application? Any specific reason you are considering the ISO7641FC and not the ISO7741 or ISO7841 family?

    Regards,
    Abhi

  • Guru 16855 points

    In reply to Abhi Aarey:

    Abhi-san

    Thank you for your information.

    Does it mean that ISO7641FC and ISO7420FC is same life characteristics(?)?
    Actual working voltage is 63Vpk.
    Do you know life expectancy in the case?

    Best Regards,
    Kuramochi
  • In reply to TQ:

    Hi Kuramochi-san,

    No I didn't meant that - I suggested ISO77XX family and ISO78XX family because they have high lifetime and good  working voltage capability.

    For ISO7641FC, the only data we have is average lifetime

    For an actual working voltage of 63V, the average  lifetime expectancy for the ISO7641FC is ~285.38 years  [ 9 * 1E9 seconds].

    Hope this helps!

    Thank you,

    Abhi

  • Guru 16855 points

    In reply to Abhi Aarey:

    Abhi-san,

    I got request from the customer.
    Could you show me equation of the average lifetime?
    They seem to want to know how to calculate lifetime.

    Best Regards,
    Kuramochi
  • Guru 16855 points

    In reply to TQ:

    Abhi-san,

    How is this progress?

    Best Regards.
    Kuramochi
  • In reply to TQ:

    Hi Kuramochi-san,

    Apologies for the delay in response, Abhi-san has been on travel for last several days hence couldn't respond. I have responded to your other related post that you have created recently. For completeness, I am copying my response below as well. Thanks.

    We do not have any equation for the average lifetime of ISO7641FC. The lifetime plot that we provide is generating from the lifetime test called Time Dependent Dielectric Breakdown (TDDB) which is a standard test practiced in the industry to find out device's lifetime.

    The basic test methodology is to apply a stress voltage from the input to the output of the DUT in a two-terminal configuration using a high-voltage source, while maintaining the still-air, ambient-air temperature at 150°C. The start of the test activates a timer; this timer is stopped when the current in the circuit exceeds a particular fail current level (like 100uA), which meant that the dielectric had failed. The time taken by device is noted for each applied test voltage. DUTs were tested independently of each other (one DUT per test) at each test voltage to get statistically valid results. Sufficient number of devices are tested at multiple test voltages to get the most practical device lifetime curve.


    Regards,
    Koteshwar Rao