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Offset shift TLV2451

Other Parts Discussed in Thread: TLV2451

Hi

We have problem with TLV2451ID that it will be a offsetshift på 70-80 uV when they have been in cold.

Question

  1. Are there any effects that can cause permanent change of offset voltage if the device is powered in a temperature  -40°C and/ or storage down to -55°C?
  2. Does temperature dependent parameters have any form of hysteresis that can give permanent changes to the value in room temperature?
  3. Do you have any studies of drift of devices being subjected to low temperatures either in operation or storage? Can the results be shared?

 KC

  • Hi KC,

    Here are my thoughts about your questions:

     

    • Are there any effects that can cause permanent change of offset voltage if the device is powered in a temperature  -40°C and/ or storage down to -55°C?

    The silicon structure comprising the TLV2451 should be stable at -55C even though the ID is rated at 0C when powered. It should be stable as well to the -65 C storage temperature. There is nothing about the TLV2451 die that should change permanently because of temperature exposure.

    • Does temperature dependent parameters have any form of hysteresis that can give permanent changes to the value in room temperature?

    The TLV2451 uses a bipolar NPN/PNP input stage followed by CMOS stages. The resistors are all diffused type resistors with trimming. Therefore, the parameters should be stable and return to value at room temperature after temperature changes.

    • Do you have any studies of drift of devices being subjected to low temperatures either in operation or storage? Can the results be

    We do not have any such reports for the TLV2451. I am currently traveling and don't have access to any sort of data. I will check with our quality department when I return to work on Monday and see if they have any such information for any devices.

    Regards, Thomas

    PA - Linear Applications Engineering

     

  • KC,

    I meant to say the diffused resistors are not trimmed.

    Also, sometimes when analog ICs take on parametric shifts after being subjected to cold it is attributable to a package-related issue such as moisture ingress. Often in those cases baking the device at a high temperature such as 125 C drives out the moisture and things return to their original values. That may not be the issue in the case, but this has been observed on various analog ICs across the years.

    Regards, Thomas

    PA - Linear Applications Engineering

  • KC,

    I went over to our QC and FA departments and discussed the cold, offset shift issue being observed with the TLV2451ID. There was complete agreement that nothing from a semiconductor physics standpoint would explain the shift. The primary cause of such shifts are due to moisture ingress into the package - as I had mentioned previously. The cause is sometimes due to package delamination allowing moisture to migrate inside and depositing on the integrated circuit die. The moisture is not pure water and often picks up ionic contamination from the leads, soldering and cleaning materials, package, and other foreign material that is present. Once on the die the ions cause surface effects, slightly altering the electrical behavior of the circuit over which they reside.

    Can you explain the sequence of events the TLV2451ID is being subjected to that results in the offset voltage shifts? We need to know the circuit, PC board information, environmental conditions, temperature cycling, electrical operating conditions and measurement systems.

    Regards, Thomas

    PA - Linear Applications Engineering 

  • Hi

    Can I send information to you that will not be puplicly.

    /kent

  • Hi Kent,

    I have received the TLV2451 confidential information from Anders and we will now handle it off the E2E forum.

    Regards, Thomas

    PA - Linear Applications Engineering