MAX3248EEAI-T Maxim Integrated, MAX3248EEAI-T Datasheet - Page 9

• Manufacturer Part Number: MAX3248EEAI-T
• Description: RS-232 Interface IC
• Manufacturer: Maxim Integrated
• Series: MAX3238E, MAX3248Er

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 MAX3238E/MAX3248E
Figure 4a. Receiver Positive/Negative Thresholds for INVALID
Figure 4b. AutoShutdown Plus and INVALID Timing Diagram
+3.0V to +5.5V, 10nA, 250kbps RS-232 Transceivers
+2.7V
+0.3V
-0.3V
-2.7V
OUTPUT
**ANY ONE RECEIVER/TRANSMITTER BECOMES ACTIVE
INVALID
*ALL RECEIVERS/TRANSMITTERS INACTIVE
TRANSMITTER
TRANSMITTER
0V
RECEIVER
OUTPUTS
VOLTAGE
VOLTAGE
VOLTAGE
INPUTS
INPUTS
V
V
with ±15kV ESD-Protected I/O and Logic Pins
CC
V+
CC
V-
0
0
_______________________________________________________________________________________
I
NVL
INDETERMINATE
INDETERMINATE
*
INVALID HIGH
INVALID HIGH
INVALID LOW
**
INVALID
REGION
IEC 1000-4-2
t
AUTOSHDN
help you design equipment that meets Level 4 (the high-
est level) of IEC 1000-4-2, without additional ESD pro-
tection components.
The major 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 6a),
the ESD withstand voltage measured to this standard is
generally lower than that measured using the Human
Body Model. Figure 6b shows the current waveform for
the ±8kV IEC 1000-4-2 Level 4 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.
The Machine Model for ESD testing uses a 200pF stor-
age capacitor and zero-discharge resistance. Its objec-
tive is to mimic the stress caused by contact that
occurs with handling and assembly during manufactur-
ing. Of course, all pins (not just RS-232 inputs and out-
puts) require this protection during manufacturing.
t
WU
t
AUTOSHDN
FORCEON = GND, FORCEOFF = V
t
WU
Machine Model
CC
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