
3
Exar Corporation 48720 Kato Road, Fremont CA, 94538 (50)668-707 www.exar.com
SP3203E_00_2080
DEVICE PIN
HUMAN BODY
IEC61000-4-2
TESTED
MODEL
Air Discharge
Direct Contact
Level
Driver Outputs
±5kV
±8kV
4
Receiver Inputs
±5kV
±8kV
4
The circuit model in Figures and 2 repre-
sent the typical ESD testing circuit used for
all three methods. The C
S is initially charged
with the DC power supply when the first
switch (SW) is on. Now that the capacitor
is charged, the second switch (SW2) is on
while SW switches off. The voltage stored
in the capacitor is then applied through R
S,
the current limiting resistor, onto the device
under test (DUT). In ESD tests, the SW2
switch is pulsed so that the device under
test receives a duration of voltage.
For the Human Body Model, the current
limitingresistor(R
S) and the source capacitor
(C
S) are 1.5k an 100pF, respectively. For
IEC-000-4-2, the current limiting resistor
(R
S) and the source capacitor (CS) are 330
an 50pF, respectively.
The higher C
S value and lower RS value in
the IEC6000-4-2 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.
Figure 3. ESD Test Waveform for IEC6000-4-2
t=0ns
t=30ns
0A
5A
30A
t →
i→
Figure 2. ESD Test Circuit for IEC6000-4-2
Table 4. Transceiver ESD Tolerance Levels