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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
DESCRIPTION
• +5V Only
• Low Power BiCMOS
• Driver / Receiver Enable for Multi-Drop
Congurations
• Enhanced ESD Specications:
+/-15kV Human Body Model
+/-15kV IEC61000-4-2 Air Discharge
+/-8kV IEC61000-4-2 Contact Discharge
• Low EMI Transceiver limited to 250kbps
• Low Power 1µA Shutdown Mode
SP483E
Enhanced Low EMI Half-Duplex
RS-485 Transceiver
The SP483E is a half-duplex transceiver that meets the specications of RS-485 and RS-422
serial protocols with enhanced ESD performance. The ESD tolerance has been improved on
these devices to over +15kV for both Human Body Model and IEC61000-4-2 Air Discharge
Method. This devices is pin-to-pin compatible with Exar's SP483 device as well as popular
industry standards. As with the original versions, the SP483E feature Exar's BiCMOS de-
sign allowing low power operation without sacricing performance. The SP483E is internally
slew rate limited to reduce EMI and can meet the requirements of RS-485 and RS-422 up to
250kbps. The SP483E is also equipped with a low power shutdown mode.
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only and functional operation
of the device at these ratings or any other above those
indicated in the operation sections of the specications
below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may
affect reliability.
VCC.......................................................................+7V
Input Voltages
Logic.........................-0.3V to (Vcc + 0.5V)
Drivers......................-0.3V to (Vcc + 0.5V)
Receivers.........................................+/-15V
ELECTRICAL CHARACTERISTICS
TMIN to TMAX and VCC = +5.0V +/-5% unless otherwise noted.
PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
SP483E DRIVER
DC Characteristics
Differential Output Voltage GND Vcc Volts Unloaded; R = ∞ ; See Figure 1
Differential Output Voltage 2 Vcc Volts With Load; R = 50Ω (RS-422);
See Figure 1
Differential Output Voltage 1.5 Vcc Volts With Load; R = 27Ω (RS-485);
See Figure 1
Change in Magnitude of Driver
Differential Output Voltage for
Complimentary states
0.2 Volts R = 27Ω or R = 50Ω; See Figure 1
Driver Common Mode Output
Voltage
3Volts R = 27Ω or R = 50Ω; See Figure 1
Input High Voltage 2.0 Volts Applies to DE, DI, RE
Input Low Voltage 0.8 Volts Applies to DE, DI, RE
Input Current, Driver Input 10 µA Applies to DI
Input Current, Control Lines 1 µA Applies to DE, RE
Driver Short Circuit Current
VOUT = HIGH +/-250 mA -7V ≤ VO ≤ +12V
VOUT = LOW +/-250 mA -7V ≤ VO ≤ +12V
SP483E DRIVER
AC Characteristics
Max. Transmission Rate 250 kbps RE = 5V, DE = 5V; RDIFF = 54Ω,
CL1 = CL2 = 100pF
Driver Input to Output, tPLH 250 800 2000 ns See Figures 3 & 5, RDIFF = 54Ω,
CL1 = CL2 = 100pF
Driver Input to Output, tPHL 250 800 2000 ns See Figures 3 & 5, RDIFF = 54Ω,
CL1 = CL2 = 100pF
Driver Skew 100 800 ns See Figures 3 and 5,
tSKEW = |tDPHL - tDPLH|
Driver Rise or Fall Time 250 2000 ns From 10%-90%; RDIFF = 54Ω
CL1 = CL2 = 100pF;
See Figures 3 and 6
Output Voltages
Logic.........................-0.3V to (Vcc + 0.5V)
Drivers.............................................+/-15V
Receivers..................-0.3V to (Vcc + 0.5V)
Storage Temperature.......................-65˚C to +150˚C
Power Dissipation..........................................500mW
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
SP483E DRIVER (continued)
AC Characteristics
Driver Enable to Output High 250 2000 ns CL = 100pF, See Figures 4 and 6,
S2 closed
Driver Enable to Output Low 250 2000 ns CL = 100pF, See Figures 4 and 6,
S1 closed
Driver Disable Time from High 300 3000 ns CL = 15pF, See Figures 4 and 6,
S2 closed
Driver Disable Time from Low 300 3000 ns CL = 15pF, See Figures 4 and 6,
S1 closed
SP483E RECEIVER
DC Characteristics
Differential Input Threshold -0.2 +0.2 Volts -7V ≤ VCM ≤ +12V
Input Hysteresis 20 mV VCM = 0V
Output Voltage High 3.5 Volts IO = -4mA, VID = +200mV
Output Voltage Low 0.4 Volts IO = +4mA, VID = +200mV
Three-State ( High Impedance)
Output Current
+/-1 µA 0.4V ≤ VO ≤ 2.4V; RE = 5V
Input Resistance 12 15 kΩ -7V ≤ VCM ≤ +12V
Input Current (A, B); VIN = 12V +1.0 mA DE = 0V, VCC = 0V or 5.25V,
VIN = 12V
Input Current (A, B); VIN = -7V -0.8 mA DE = 0V, VCC = 0V or 5.25V,
VIN = -7V
Short Circuit Current 7 95 mA 0V ≤ VO ≤ VCC
SP483E RECEIVER
AC Characteristics
Max. Transmission Rate 250 kbps RE = 0V, DE = 0V
Receiver Input to Output 250 2000 ns tPLH ; See Figures 3 & 7,
RDIFF = 54Ω, CL1 = CL2 = 100pF
Receiver Input to Output 250 2000 ns tPHL ; See Figures 3 & 7,
RDIFF = 54Ω, CL1 = CL2 = 100pF
Differential Receiver Skew
|tPHL - tPLH|
100 ns RDIFF = 54Ω, CL1 = CL2 = 100pF,
See Figures 3 and 7
Receiver Enable to Output Low 45 70 ns CRL = 15pF, Figures 2 & 8;
S1 Closed
Receiver Enable to Output High 45 70 ns CRL = 15pF, Figures 2 & 8;
S2 Closed
Receiver Disable from LOW 45 70 ns CRL = 15pF, Figures 2 & 8;
S1 Closed
Receiver Disable from High 45 70 ns CRL = 15pF, Figures 2 & 8;
S2 Closed
ELECTRICAL CHARACTERISTICS
TMIN to TMAX and VCC = +5.0V +/-5% unless otherwise noted.
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
SP483E
Shutdown Timing
Time to Shutdown 50 200 600 ns RE = 5V, DE = 0V
Driver Enable from Shutdown
to Output High
2000 ns CL = 100pF; See Figures 4 and 6;
S2 Closed
Driver Enable from Shutdown
to Output Low
2000 ns CL = 100pF; See Figures 4 and 6;
S1 Closed
Receiver Enable from
Shutdown to Output High
300 2500 ns CL = 15pF; See Figures 2 and 8; S2
Closed
Receiver Enable from
Shutdown to Output Low
300 2500 ns CL = 15pF; See Figures 2 and 8; S1
Closed
POWER REQUIREMENTS
Supply Voltage VCC +4.75 +5.25 Volts
Supply Current
No Load 900 µA RE, DI = 0V or VCC; DE = VCC
600 µA RE = 0V, DI = 0V or 5V; DE = 0V
Shutdown Mode 1 10 µA DE = 0V, RE = VCC
ENVIRONMENTAL AND MECHANICAL
Operating Temperature
Commercial (_C_) 0 70 ºC
Industrial (_E_) -40 +85 ºC
Storage Temperature -65 +150 ºC
Package
Plastic DIP (_P)
NSOIC (_N)
ELECTRICAL CHARACTERISTICS
TMIN to TMAX and VCC = +5.0V +/-5% unless otherwise noted.
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
PIN FUNCTION
TEST CIRCUITS
A
B
R
R
V
OD
V
OC
Figure 1. RS-485 Driver DC Test Load Circuit
CL1
15pF
RO
A
B
A
B
DI
CL2
RDIFF
Figure 3. RS-485 Driver/Receiver Timing Test
500Ω
CL
Output
Under
Test
S1
S2
VCC
Figure 4. Driver Timing Test Load #2 Circuit
Figure 2. Receiver Timing Test Load Circuit
1kΩ
1kΩCRL
Receiver
Output S1
S2
Test Point
VCC
Pin 1 - RO - Receiver Output
Pin 2 - RE - Receiver Output Enable Active LOW
Pin 3 - DE - Driver Output Enable Active HIGH
Pin 4 - DI - Driver Input
Pin 5 - GND - Ground Connection
Pin 6 - A - Driver Output / Receiver input
Non-Inverting
Pin 7 - B - Driver Output / Receiver Input Inverting
Pin 8 - Vcc - Positive Supply 4.75V ≤ Vcc ≤ 5.25V
Figure 5. Driver Propagation Delays
+3V
0V
DRIVER INPUT
A
B
DRIVER
OUTPUT
VO+
DIFFERENTIAL
OUTPUT
VA – VB
0V
VO–
1.5V 1.5V
tPLH
tF
tR
tR
≤ 10ns;
tF ≤ 10ns
VO1/2V
O1/2V
O
tPHL
tSKEW
= |tDPLH
- tDPHL|
tDPLH tDPHL
f =
100kHz;
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
Figure 6. Driver Enable and Disable Times
Figure 8. Receiver Enable and Disable Times
+3V
0V
DE
5V
VOL
A
, B
0V
1.5V 1.5V
tZL
tZH
f = 100kHz; tR
< 10ns; tF < 10ns
VOH
A
, B 2.3V
2.3V
tLZ
tHZ
0.5V
0.5V
Output normally LOW
Output normally HIGH
SWITCHING WAVEFORMS
FUNCTION TRUTH TABLES
INPUTS OUTPUTS
RE DE DI
LINE
CONDITION A B
X 1 1 No Fault 1 0
X 1 0 No Fault 0 1
X 0 X X Z Z
X 1 X Fault Z Z
Table 1. Transmit Function Truth Table
INPUTS OUTPUTS
RE DE A - B R
0 0 +0.2V 1
0 0 -0.2V 0
0 0 Inputs Open 1
1 0 X Z
Table 2. Receive Function Truth Table
V
OH
V
OL
R1.5V 1.5V
t
PHL
f = 100kHz; t
R
10ns; t
F
≤ 10ns
OUTPUT
V
OD2
+
V
OD2
–
A
– B 0V 0V
t
PLH
INPUT
≤
t = | t - t |
SKEW PHL PLH
+3V
0V
5V
0V
1.5V 1.5V
t
ZL
t
ZH
f = 100kHz; t
R
≤ 10ns; t
F
≤ 10ns
R1.5V
1.5V
t
LZ
t
HZ
0.5V
0.5V
Output normally LOW
Output normally HIGH
V
IL
V
IH
R
RE
Figure 7. Receiver Propagation Delays
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
The SP483E is a half-duplex differential
transceiver that meets the requirements
of RS-485 and RS-422. Fabricated with
an Exar proprietary BiCMOS process, this
product requires a fraction of the power of
older bipolar designs.
The RS-485 standard is ideal for multi-drop
applications and for long-distance interfaces.
RS-485 allows up to 32 drivers and 32 receiv-
ers to be connected to a data bus, making it
an ideal choice for multi-drop applications.
Since the cabling can be as long as 4,000
feet, RS-485 transceivers are equipped with
a wide (-7V to +12V) common mode range
to accommodate ground potential differ-
ences. Because RS-485 is a differential
interface, data is virtually immune to noise
in the transmission line.
Drivers
The driver outputs of the SP483E are dif-
ferential outputs meeting the RS-485 and
RS-422 standards. The typical voltage
output swing with no load will be 0 Volts to
+5 Volts. With worst case loading of 54Ω
across the differential outputs, the drivers
can maintain greater than 1.5V voltage
levels. The drivers have an enable control
line which is active HIGH. A logic HIGH on
DE (pin 3) will enable the differential driver
outputs. A logic LOW on the DE (pin 3) will
tri-state the driver outputs.
The SP483E has internally slew rate lim-
ited driver outputs to minimize EMI. The
maximum data rate for the SP483E drivers
is 250kbps under load.
Receivers
The SP483E receivers have differential
inputs with an input sensitivity as low as
±200mV. Input impedance of the receivers is
typically 15kΩ (12kΩ minimum). A wide com-
mon mode range of -7V to +12V allows for
large ground potential differences between
systems. The receivers have a tri-state en-
able control pin. A logic LOW on RE (pin 2)
will enable the receiver, a logic HIGH on RE
(pin 2) will disable the receiver.
The SP483E receiver is rated for data
rates up to 250kbps. The receivers are
equipped with the fail-safe feature. Fail-
safe guarantees that the receiver output
will be in a HIGH state when the input is
left unconnected.
Shutdown Mode
The SP483E is equipped with a Shutdown
mode. To enable the shutdown state, both
driver and receiver must be disabled simul-
taneously. A logic LOW on DE (pin 3) and a
Logic HIGH on RE (pin 2) will put the SP483E
into Shutdown mode. In Shutdown, supply
current will drop to typically 1µA.
ESD TOLERANCE
The SP483E incorporates ruggedized ESD
cells on all driver output and receiver input
pins. The ESD structure is improved over our
previous family for more rugged applications
and environments sensitive to electro-static
discharges and associated transients. The
improved ESD tolerance is at least ±15kV
without damage or latch-up.
There are different methods of ESD testing
applied:
a) MIL-STD-883, Method 3015.7
b) IEC61000-4-2 Air-Discharge
c) IEC61000-4-2 Direct Contact
DESCRIPTION
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
The Human Body Model has been the
generally accepted ESD testing method
for semiconductors. This method is also
specied 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 9. This method will test the IC’s
capability to withstand an ESD transient dur-
ing normal handling such as in manufactur-
ing areas where the IC's tend to be handled
frequently. The IEC61000-4-2, formerly
IEC801-2, is generally used for testing ESD
on equipment and systems.
For system manufacturers, they must guar-
antee a certain amount of ESD protection
since the system itself is exposed to the
outside environment and human presence.
The premise with IEC61000-4-2 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 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 IEC61000-4-2 is shown on Figure 10.
There are two methods within IEC61000-4-2,
the Air Discharge method and the Contact
Discharge method.
Figure 9. ESD Test Circuit for Human Body Model
Figure 10. ESD Test Circuit for IEC61000-4-2
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
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
nd 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 situ-
ations 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 nally to the IC.
The circuit model in Figures 9 and 10 repre-
sent the typical ESD testing circuit used for
all three methods. The CS is initially charged
with the DC power supply when the rst
switch (SW1) is on. Now that the capacitor
is charged, the second switch (SW2) is on
while SW1 switches off.
t = 0ns t = 30ns
0A
15A
30A
I →
t →
Figure 11. ESD Test Waveform for IEC61000-4-2
The voltage stored in the capacitor is then
applied through RS, the current limiting
resistor, onto the device under test (DUT).
In ESD tests, the SW2 switch is pulsed so
that the device under test receives a dura-
tion of voltage.
For the Human Body Model, the current
limiting resistor (RS) and the source capacitor
(CS) are 1.5kΩ an 100pF, respectively. For
IEC-61000-4-2, the current limiting resistor
(RS) and the source capacitor (CS) are 330Ω
an 150pF, respectively.
The higher CS value and lower RS value in
the IEC61000-4-2 model are more stringent
than the Human Body Model. The larger
storage capacitor injects a higher voltage
to the test point when SW2 is switched on.
The lower current limiting resistor increases
the current charge onto the test point.
DEVICE PIN
TESTED
HUMAN BODY
MODEL
IEC61000-4-2
Air Discharge Direct Contact Level
Driver Outputs
Receiver Inputs
+/-15kV
+/-15kV
+/-15kV
+/-15kV
+/-8kV
+/-8kV
4
4
Table 1. Transceiver ESD Tolerance levels
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP483E_100_020912
ORDERING INFORMATION
Model Temperature Range Package Types
SP483ECN-L ....................................................................... 0°C to +70°C ................................................................................................8-pin NSOIC
SP483ECN-L/TR ................................................................. 0°C to +70°C ................................................................................................8-pin NSOIC
SP483EEN-L.................................................................... -40°C to +85°C...............................................................................................8-pin NSOIC
SP483EEN-L/TR................................................................. -40°C to +85°C.............................................................................................8-pin NSOIC
SP483ECP-L ....................................................................... 0°C to +70°C ...................................................................................................8-pin PDIP
SP483EEP-L.................................................................... -40°C to +85°C...................................................................................................8-pin PDIP
REVISION HISTORY
DATE REVISION DESCRIPTION
2000 05 Legacy Sipex Datasheet
02/09/12 1.0.0 Convert to Exar Format. Update ordering information. Change ESD specication to
IEC61000-4-2.
Notice
EXAR Corporation reserves the right to make changes to any products contained in this publication in order to improve design, performance or reliabil-
ity. EXAR Corporation assumes no representation that the circuits are free of patent infringement. Charts and schedules contained herein are only for
illustration purposes and may vary depending upon a user's specic application. While the information in this publication has been carefully checked;
no responsibility, however, is assumed for inaccuracies.
EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can
reasonably be expected to cause failure of the life support system or to signicantly affect its safety or effectiveness. Products are not authorized for
use in such applications unless EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been
minimized ; (b) the user assumes all such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances.
Copyright 2012 EXAR Corporation
Datasheet February 2012
Send your serial transceiver technical questions with technical details to: serialtechsupport@exar.com
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