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  1.   Trademarks
  2. 1Introduction
  3. 2IEEE Specification and How to Derive the Formula
  4. 3Formula Helper to Calculate Limit
  5. 4Conclusion and Summary
  6. 5References

3 Formula Helper to Calculate Limit

The following formula can be copied into a Microsoft® Excel file. With this helper the engineer can validate if the test equipment vendor is using the correct percent error formula:


GUID-20210719-CA0I-LTMF-5TQK-GRP7RPVLSHR8-low.png

Va = 695.89 mV

Vb = 708.24 mV

=100*((B2-0.5*(B1+B2))/(0.5*(B1+B2)))


GUID-20210719-CA0I-5WVL-Z9XS-HRQ3JGL3MVTV-low.png

Figure 3-1 Formula in Microsoft® Excel

The result in the Excel table cell B3 reports that the test result has been passed because it is below 1%. The test report from the test equipment vendor shows a failed test case. In this case the formula used in Figure 1-1 by the manufacturer is incorrect and out-of-date. When facing this situation, contact the test manufacturer for a software update.