Datasheet

ESD protection can be tested in various ways; the trans-
mitter outputs and receiver inputs of this product family
are characterized for protection to the following limits:
1) ±15kV using the Human Body Model
2) ±8kV using the Contact Discharge Method specified
in IEC1000-4-2
3) ±15kV using IEC1000-4-2’s Air-Gap Method
EESSDD TTeesstt CCoonnddiittiioonnss
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents
test setup, test methodology, and test results.
HHuummaann BBooddyy MMooddeell
Figure 6a shows the Human Body Model, and Figure
6b 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 test device through a
1.5kΩ resistor.
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 MAX3221E/ MAX3223E/
MAX3243E help you design equipment that meets
V-
V
CC
0
V+
0
V
CC
t
INVL
t
WU
INVALID
REGION
RECEIVER
INPUT
VOLTAGE
(V)
INVALID
OUTPUT
(V)
t
INVH
TRANSMITTERS ENABLED, INVALID HIGH
RECEIVER INPUT LEVELS
AUTOSHUTDOWN, TRANSMITTERS DISABLED,
1µA SUPPLY CURRENT, INVALID LOW
TRANSMITTERS ENABLED, INVALID HIGH
-2.7V
-0.3V
+2.7V
+0.3V
0
INDETERMINATE
INDETERMINATE
b)
a)
Figure 5. AutoShutdown Trip Levels
FORCEON
MASTER SHDN LINE
0.1µF1MΩ
FORCEOFF
MAX3221E
MAX3223E
MAX3243E
POWER-
MANAGEMENT
UNIT
Figure 4. AutoShutdown with Initial Turn-On to Wake Up a
Mouse or Another System
FORCEOFF
POWER DOWN
INVALID
FORCEON
INVALID IS AN INTERNALLY GENERATED SIGNAL
THAT IS USED BY THE AUTOSHUTDOWN LOGIC
AND APPEARS AS AN OUTPUT OF THE DEVICE.
POWER DOWN IS ONLY AN INTERNAL SIGNAL.
IT CONTROLS THE OPERATIONAL STATUS OF
THE TRANSMITTERS AND THE POWER SUPPLIES.
Figure 3c. MAX32_ _E AutoShutdown Logic
Table 2. INVALID Truth Table
LowNo
HighYes
INVALID OUTPUT
RS-232 SIGNAL PRESENT
AT ANY RECEIVER INPUT
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown
10
Maxim Integrated
MAX3221E/MAX3223E/MAX3243E