SP3243EET-L Exar Corporation, SP3243EET-L Datasheet - Page 16

• Manufacturer Part Number: SP3243EET-L
• Description: IC TXRX RS232 INTELLIGNT 28WSOIC
• Manufacturer: Exar Corporation
• Type: Transceiverr

Specifications of SP3243EET-L

• Package / Case: 28-SOIC (0.300", 7.50mm Width)
• Number Of Drivers/receivers: 3/5
• Protocol: RS232
• Voltage - Supply: 3 V ~ 5.5 V
• Mounting Type: Surface Mount
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Function: Transceiver
• Mounting Style: SMD/SMT
• Supply Current: 1 uA
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 3 V
• Logic Type: RS-232 Transceivers
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 1016-1122-5

ESD TOLERANCE
The SP3243 series incorporates ruggedized ESD
cells on all driver output and receiver input pins.
The ESD structure is improved over our previ-
ous family for more rugged applications and
environments sensitive to electro-static dis-
charges and associated transients. The improved
ESD tolerance is at least +15kV without damage
nor latch-up.
There are different methods of ESD testing
applied:
The Human Body Model has been the generally
accepted ESD testing method for semi-
conductors. This method is also specified in
MIL-STD-883, Method 3015.7 for ESD testing.
The premise of this ESD test is to simulate the
human body’s potential to store electro-static
energy and discharge it to an integrated circuit.
The simulation is performed by using a test
model as shown in Figure 30. This method will
test the IC’s capability to withstand an ESD
transient during normal handling such as in
manufacturing areas where the ICs tend to be
handled frequently.
The IEC-1000-4-2, formerly IEC801-2, is
generally used for testing ESD on equipment and
systems. For system manufacturers, they must
guarantee a certain amount of ESD protection
since the system itself is exposed to the outside
environment and human presence. The premise
with IEC1000-4-2 is that the system is required
to withstand an amount of static electricity when
ESD is applied to points and surfaces of the
equipment that are accessible to personnel during
Figure 30. ESD Test Circuit for Human Body Model
Date: 2/05/06
a) MIL-STD-883, Method 3015.7
b) IEC1000-4-2 Air-Discharge
c) IEC1000-4-2 Direct Contact
DC Power
Source
R
R R
C
C C
SP3243 +3.0V to +5.5V RS-232 Transceivers
SW1
SW1
SW1
16
C
C C
S
S S
normal usage. The transceiver IC receives most
of the ESD current when the ESD source is
applied to the connector pins. The test circuit for
IEC1000-4-2 is shown on Figure 31. There are
two methods within IEC1000-4-2, the Air
Discharge method and the Contact Discharge
method.
With the Air Discharge Method, an ESD voltage
is applied to the equipment under test (EUT)
through air. This simulates an electrically charged
person ready to connect a cable onto the rear of
the system only to find an unpleasant zap just
before the person touches the back panel. The
high energy potential on the person discharges
through an arcing path to the rear panel of the
system before he or she even touches the system.
This energy, whether discharged directly or
through air, is predominantly a function of the
discharge current rather than the discharge
voltage. Variables with an air discharge such as
approach speed of the object carrying the ESD
potential to the system and humidity will tend to
change the discharge current. For example, the
rise time of the discharge current varies with the
approach speed.
The Contact Discharge Method applies the ESD
current directly to the EUT. This method was
devised to reduce the unpredictability of the
ESD arc. The discharge current rise time is
constant since the energy is directly transferred
without the air-gap arc. In situations such as
hand held systems, the ESD charge can be directly
discharged to the equipment from a person already
holding the equipment. The current is transferred
on to the keypad or the serial port of the equipment
directly and then travels through the PCB and finally
to the IC.
R
R R
S
S S
SW2
SW2
SW2
Device
Under
Test
© Copyright 2006 Sipex Corporation