MAX3209E Maxim, MAX3209E Datasheet - Page 5

• Manufacturer Part Number: MAX3209E
• Description: 15kV ESD-Protected / 12V / Dual RS-232 Serial Port with Low-Power Standby for Motherboards/Desktops
• Manufacturer: Maxim

As with all Maxim devices, ESD-protection structures
are incorporated on all pins to protect against electro-
static discharges (ESD) encountered during handling
and assembly. The MAX3209E driver outputs and
receiver inputs have extra protection against static
electricity found in normal operation. Maxim’s engineers
developed state-of-the-art structures to protect these
pins against ±15kV ESD, without damage. After an ESD
event, the MAX3209E continues working without latchup.
ESD protection can be tested in several ways. The
transmitter outputs and receiver inputs are character-
ized for protection to the following:
1) ±15kV using the Human Body Model
2) ±8kV using the Contact-Discharge Method specified
3) ±15kV using the Air-Gap Method specified in
ESD performance depends on a number of conditions.
Contact Maxim for a reliability report that documents
test setup, methodology, and results.
Figure 2a shows the Human Body Model, and Figure
2b shows the current waveform it generates when dis-
charged into a low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which is then discharged into the device through a
1.5kΩ resistor.
Since January 1996, all equipment manufactured
and/or sold in the European community has been
required to meet the stringent IEC 1000-4-2 specifica-
tion. The IEC 1000-4-2 standard covers ESD testing
and performance of finished equipment; it does not
specifically refer to integrated circuits. The MAX3209E
helps you design equipment that meets Level 4 (the
highest level) of IEC 1000-4-2, without additional ESD-
protection components.
The main difference between tests done using the
Human Body Model and IEC 1000-4-2 is higher peak
current in IEC 1000-4-2. Because series resistance is
lower in the IEC 1000-4-2 ESD test model (Figure 3a), the
ESD withstand voltage measured to this standard is gen-
erally lower than that measured using the Human Body
Model. Figure 3b shows the current waveform for the
±8kV IEC 1000-4-2 Level 4 ESD Contact-Discharge test.
with Low-Power Standby for Motherboards/Desktops
in IEC 1000-4-2 (formerly IEC 801-2)
IEC 1000-4-2 (formerly IEC 801-2)
±15kV ESD-Protected, 12V, Dual RS-232 Serial Port
_______________________________________________________________________________________
Detailed Description
±15kV ESD Protection
ESD Test Conditions
Human Body Model
IEC 1000-4-2
The Air-Gap test involves approaching the device with a
charge probe. The Contact-Discharge method connects
the probe to the device before the probe is energized.
Figure 2b. Human Body Model Current Waveform
Figure 2a. Human Body ESD Test Model
Figure 3a. IEC 1000-4-2 ESD Test Model
AMPERES
VOLTAGE
SOURCE
VOLTAGE
HIGH-
SOURCE
DC
HIGH-
DC
I
P
36.8%
100%
90%
10%
CHARGE-CURRENT
CHARGE-CURRENT
LIMIT RESISTOR
0
LIMIT RESISTOR
0
50M to 100M
1M
t
R
RL
R
C
100pF
C
150pF
C s
C s
STORAGE
CAPACITOR
CURRENT WAVEFORM
STORAGE
CAPACITOR
TIME
1500
RESISTANCE
DISCHARGE
RESISTANCE
DISCHARGE
R
330
D
R
t
DL
D
I r
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
DEVICE
UNDER
DEVICE
UNDER
TEST
TEST
5