DocID022589 Rev 2

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AN4022

Predicted results versus measured results

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The device under test is measured in ESD clamping test at the different standard voltage

levels, as in Figure 12 (example at +8 kV). The test conditions used are described in the

STMicroelectronics Application note AN3353, “IEC 61000-4-2 standard testing”.

Figure 12. Typical clamping voltage waveform with the measured values

We get from these waveforms three values: the peak clamping voltage (first spike) and the

clamping voltages at t = 30 ns and t = 60 ns at peak charging voltage of

±2 kV, ±4 kV, ±6 kV

and

±8 kV. The values at the add point ±15 kV was also obtained, even if this point is not

specified in the standard.

We can now represent in three charts the predicted values and the real measurement

results in order to compare them.

Figure 13. Measurements and predicted values for the first spike peak value

t=30 ns

t=60 ns

Predicted peak min

Predicted peak typical

Predicted peak max

Measured peak

VCL (V)

Breakdown

VPP (kV)

0

2

4

6

8

101214

16

0

10

20

30

40

50

60

70