Datasheet

±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
ESD protection can be tested in various ways; the
transmitter outputs and receiver inputs for the
MAX3222E/MAX3232E/MAX3241E/MAX3246E are
characterized for protection to the following limits:
• ±15kV using the Human Body Model
• ±8kV using the Contact Discharge method specified
in IEC 1000-4-2
• ±9kV (MAX3246E only) using the Contact Discharge
method specified in IEC 1000-4-2
• ±15kV using the Air-Gap Discharge method speci-
fied in IEC 1000-4-2
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
C
s
100pF
R
C
1MΩ
R
D
1500Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE-
UNDER-
TEST
Figure 4a. Human Body ESD Test Model
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
Figure 4b. Human Body Model Current Waveform
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
C
s
150pF
R
C
50MΩ to 100MΩ
R
D
330Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE-
UNDER-
TEST
Figure 5a. IEC 1000-4-2 ESD Test Model
t
r
= 0.7ns to 1ns
30ns
60ns
t
100%
90%
10%
I
PEAK
I
Figure 5b. IEC 1000-4-2 ESD Generator Current Waveform
Table 1. MAX3222E/MAX3237E/MAX3241E/
MAX3246E Shutdown and Enable Control
Truth Table
SHDN
EN
T_OUT R_OUT
R_OUTB
(MAX3237E/
MAX3241E)
0
0
High
impedance
Active Active
0
1
High
impedance
High
impedance
Active
1
0
Active Active Active
1
1
Active
High
impedance
Active
Maxim Integrated
11
MAX3222E/MAX3232E/MAX3237E/
MAX3241E/MAX3246E