ADM202E/ADM1181A
ESD TESTING (IEC1000-4-2)
IEC1000-4-2 (previously 801-2) specifies compliance testing
using two coupling methods, contact discharge and air-gap
discharge. Contact discharge calls for a direct connection to the
unit being tested. Air-gap discharge uses a higher test voltage,
but does not make direct contact with the unit being tested.
With air-gap discharge, the discharge gun is moved toward the
unit being tested, developing an arc across the air gap. This
method is influenced by humidity, temperature, barometric
pressure, distance, and rate of closure of the discharge gun.
Although less realistic, the contact-discharge method is more
repeatable and is gaining preference to the air-gap method.
Although very little energy is contained within an ESD pulse,
the extremely fast rise time coupled with high voltages can
cause failures in unprotected semiconductors. Catastrophic
destruction can occur immediately as a result of arcing or
heating. Even if catastrophic failure does not occur immediately,
the device might suffer from parametric degradation, which can
result in degraded performance. The cumulative effects of
continuous exposure can eventually lead to complete failure.
I/O lines are particularly vulnerable to ESD damage. Simply
touching or plugging in an I/O cable can result in a static
discharge, which can damage or completely destroy the
interface product connected to the I/O port. Traditional ESD
test methods, such as the MIL-STD-883B method 3015.7, do
not fully test a product’s susceptibility to this type of discharge.
This test was intended to test a product’s susceptibility to ESD
damage during handling. Each pin is tested with respect to all
other pins. There are some important differences between the
traditional test and the IEC test:
•
•
•
The IEC test is much more stringent in terms of discharge
energy. The injected peak current is over four times greater.
The current rise time is significantly faster in the IEC test.
The IEC test is carried out while power is applied to
the device.
HIGH
VOLTAGE
GENERATOR
R1
R2
DEVICE
UNDER TEST
C1
ESD TEST METHOD
H. BODY MIL-STD883B
IEC1000-4-2
R2
1.5kΩ
330Ω
C1
100pF
150pF
00066-018
Figure 18. ESD Test Standards
100
90
I
PEAK
(%)
36.8
t
RL
t
DL
TIME t
Figure 19. Human Body Model ESD Current Waveform
100
90
I
PEAK
(%)
10
00066-020
0.1 TO 1ns
30ns
60ns
TIME t
Figure 20. IEC1000-4-2 ESD Current Waveform
It is possible that the ESD discharge could induce latch-up in the
device being tested. Therefore, this test is more representative of a
real-world I/O discharge where the equipment is operating
normally with power applied. For peace of mind, however, both
tests should be performed to ensure maximum protection
during both handling and field service.
The ADM202E/ADM1181E products are tested using both of
the previously mentioned test methods. Pins are tested with
respect to all other pins as per the MIL-STD-883B specification.
In addition, I/O pins are tested as per the IEC test specification.
The products were tested under the following conditions:
•
Power-On
•
Power-Off
There are four levels of compliance defined by IEC1000-4-2. The
ADM202E/ADM1181A products meet the most stringent level
of compliance both for contact and for air-gap discharge. This
means that the products are able to withstand contact discharges
in excess of 8 kV and air-gap discharges in excess of 15 kV.
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