DocID024663 Rev 2

9/20

AN4299

Test set up proposal to detect worst case

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3

Test set up proposal to detect worst case

Most of the IEC61000-4-6 compliant generators do not offer the ability to generate a step

smaller than 1 kHz. As previously indicated, to determine the most critical noise frequency, it

is generally required to use 100 Hz steps or even 10 Hz steps. The following setup is an

alternative to find out the most critical noise frequencies and to evaluate the robustness of

the EUT at these frequencies.

Note:

The noise frequencies impacting the equipment are generally around the charge transfer

frequency and up to 40MHz. Higher noise frequency does not have an impact on the

equipment operation.

3.1

Test setup

In order to simulate a human finger, a copper coin (from10 to16 mm diameter) with a 500 Ω

serial resistor connected to GND can be used.

The CDN adaptor is the same as the one used in IEC61000-4-6.

Figure 4. Test condition