98% curves on Infineon datasheets

Discussion in 'Electronics Resources' started by Obanion, Jan 29, 2011.

  1. Obanion

    Thread Starter New Member

    Nov 26, 2009
    Hi guys,

    Does anyone happen to know what these "98%" curves are on some of the Infineon MOSFET datasheets for Rds(on) and the body diode forward voltage drop? I've checked through their documentation and I actually phoned their support number to no avail (surprisingly!)

    Please find an example here: http://www.infineon.com/dgdl/IPW60R...90004&fileId=db3a304412b407950112b42d8e55489b
    (on pages 5 and 6)

    I'm thinking it has to do with some kind of binning, but I'd like to make sure before using the numbers.

  2. bertus


    Apr 5, 2008

    I think you mean the puctures 7 and 10 of the datasheet.


    There are mosfets with a higher Rds_on as the typicalvalue.
    The 98% curve is the curve on wich 98% of the produced mosfets should match.


    Also here with the Vds, there can be samples with a higher Vds than the typical value,
    but 98% has the 98% curve as a maximum value.

  3. Papabravo


    Feb 24, 2006
    With parameters that follow a normal distribution the standard deviation tells you how far from the mean you would find typical values. If the greek letter σ represents the stndard deviation then:

    ±σ ≈ 68% of the cases
    ±2σ ≈ 95% of the cases
    ±3σ ≈ 99.7% of the cases

    So I'm guessing that 98% curves cover a range jus a bit looser than ±3σ. With a bit of effort I could tell you the exact range in terms of standard deviations.
    Last edited: Jan 29, 2011
  4. Obanion

    Thread Starter New Member

    Nov 26, 2009
    Thank you for the detailed explanation guys. Very helpful and good to know for the future. I appreciate it.