MAX3235ECWP-T Maxim Integrated, MAX3235ECWP-T Datasheet - Page 9

• Manufacturer Part Number: MAX3235ECWP-T
• Description: RS-232 Interface IC
• Manufacturer: Maxim Integrated
• Series: MAX3233E, MAX3235Er

Specifications of MAX3235ECWP-T

• Data Rate: 250 Kbps
• Operating Supply Voltage: 5 V
• Supply Current: 1 mA
• Operating Temperature Range: 0 C to + 70 C
• Mounting Style: SMD/SMT
• Function: Transceiver
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Number Of Drivers: 2
• Number Of I/os: 8
• Number Of Receivers: 2
• Propagation Delay Time Ns: 0.15 us
• Shutdown: Yes

event, Maxim’s E versions keep working without
latchup, whereas competing RS-232 products can
latch and must be powered down to remove latchup.
Figure 4. AutoShutdown Plus Initial Turn-On to Wake Up
Another System
Figure 5a. Human Body ESD Test Model
Figure 5b. Human Body Current Waveform
±15kV ESD-Protected, 1µA, 250kbps, 3.3V/5V, Dual
AMPERES
VOLTAGE
SOURCE
HIGH-
MANAGEMENT
DC
RS-232 Transceivers with Internal Capacitors
POWER-
I
P
UNIT
36.8%
100%
90%
10%
CHARGE-CURRENT
LIMIT RESISTOR
0
0
R
C
t
1MΩ
RL
100pF
MASTER SHDN LINE
_______________________________________________________________________________________
C s
STORAGE
CAPACITOR
R
CURRENT WAVEFORM
RESISTANCE
TIME
D
DISCHARGE
FORCEOFF
1500Ω
t
DL
MAX3233E
MAX3235E
I r
0.1µF
FORCEON
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
1MΩ
DEVICE
UNDER
TEST
ESD protection can be tested in various ways; the
transmitter 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
3) ±15kV using IEC 1000-4-2’s Air-Gap Discharge
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents
test setup, test methodology, and test results.
Figure 5a shows the Human Body Model and Figure 5b
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 inter-
est, which is then discharged into the test device
through a 1.5kΩ resistor.
The IEC 1000-4-2 standard covers ESD testing and per-
formance of finished equipment; it does not specifically
refer to integrated circuits. The MAX3233E/MAX3235E
help you design equipment that meets Level 4 (the high-
est level) of IEC 1000-4-2, without the need for additional
ESD-protection components.
The major difference between tests done using the
Human Body Model and IEC 1000-4-2 is higher peak cur-
rent in IEC 1000-4-2, because series resistance is lower
in the IEC 1000-4-2 model. Hence, the ESD withstand
voltage measured to IEC 1000-4-2 is generally lower than
Figure 6a. IEC 1000-4-2 ESD Test Model
VOLTAGE
SOURCE
in IEC 1000-4-2
method
HIGH-
DC
CHARGE CURRENT
R
LIMIT RESISTOR
C
50MΩ to 100MΩ
150pF
C s
STORAGE
CAPACITOR
R
RESISTANCE
DISCHARGE
D
330Ω
ESD Test Conditions
Human Body Model
IEC 1000-4-2
DEVICE
UNDER
TEST
9