Date: 06/22/04 SP3222EH/3232EH 3.3V, 460 Kbps RS-232 Transceivers
Copyright 2004 Sipex Corporation
14
Figure 19. ESD Test Waveform for IEC1000-4-2
30A
I
0A
15A
t=30ns
t
t=0ns
For the Human Body Model, the current
limiting resistor (R
) and the source capacitor
(C
) are 1.5k
an 100pF, respectively. For
IEC-1000-4-2, the current limiting resistor (R
S
)
and the source capacitor (C
S
) are 330
an 150pF,
respectively.
The higher C
value and lower R
value in the
IEC1000-4-2 model are more stringent than the
Human Body Model. The larger storage
capacitor injects a higher voltage to the test
point when SW2 is switched on. The lower
current limiting resistor increases the current
charge onto the test point.
Device Pin
Tested
Human Body
Model
IEC1000-4-2
Air Discharge Direct Contact Level
Driver Outputs
Receiver Inputs
±
15kV
±
15kV
±
15kV
±
15kV
±
8kV
±
8kV
4
4
Table 3. Transceiver ESD Tolerance Levels