Datasheet

IEC1000-4-2
The IEC1000-4-2 standard covers ESD testing and per-
formance of finished equipment; it does not specifically
refer to integrated circuits. The MAX202E/MAX203E–
MAX213E, MAX232E/MAX241E help you design equip-
ment that meets level 4 (the highest level) of IEC1000-
4-2, without the need for additional ESD-protection
components.
The major difference between tests done using the
Human Body Model and IEC1000-4-2 is higher peak cur-
rent in IEC1000-4-2, because series resistance is lower
in the IEC1000-4-2 model. Hence, the ESD withstand
voltage measured to IEC1000-4-2 is generally lower than
that measured using the Human Body Model. Figure 7b
shows the current waveform for the 8kV IEC1000-4-2
level-four ESD contact-discharge test.
The air-gap test involves approaching the device with a
charged probe. The contact-discharge method connects
the probe to the device before the probe is energized.
Machine Model
The Machine Model for ESD tests all pins using a 200pF
storage capacitor and zero discharge resistance. Its
objective is to emulate the stress caused by contact that
occurs with handling and assembly during manufacturing.
Of course, all pins require this protection during manu-
facturing, not just RS-232 inputs and outputs. Therefore,
after PC board assembly, the Machine Model is less rel-
evant to I/O ports.
Figure 6a. Human Body ESD Test Model
Figure 7a. IEC1000-4-2 ESD Test Model
Figure 7b. IEC1000-4-2 ESD Generator Current Waveform
Figure 6b. Human Body Model Current Waveform
www.analog.com
Analog Devices │ 12
MAX202E–MAX213E,
MAX232E/MAX241E
±15kV ESD-Protected,
5V RS-232 Transceivers
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
C
s
100pF
R
C
1MΩ R
D
1500Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
C
s
150pF
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
R
C
50MΩ to 100MΩ R
D
330Ω
t
r
= 0.7ns to 1ns
30ns
60ns
t
100%
90%
10%
I
PEAK
I
I
P
100%
90%
36.8%
t
RL
TIME
t
DL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
I
r
10%
0
0
AMPERES