1
SP3483 DS/04 SP3483 Low Power Slew Rate Limited Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation
SP3483
s
RS-485 and RS-422 Transceiver
s
Operates from a single +3.3V supply
s
Interoperable with +5.0V logic
s
Driver/Receiver Enable
s
Low Power Shutdown Mode
s
-7V to +12V Common-Mode Input
Voltage Range
s
Allows up to 32 transceivers on
the serial bus
s
Compatibility with the industry
standard 75176 pinout
s
Driver Output Short-Circuit Protection
s
Slew Rate Limited Driver for Low EMI
(SP3483)
8
7
6
5
1
2
3
4
Vcc
B
A
GND
D
R
RO
RE
DE
DI
SP3483
RE
DESCRIPTION
The SP3483 device is part of a family of +3.3V low power half-duplex transceivers that meet
the specifications of the RS-485 and RS-422 serial protocols. This device is pin-to-pin
compatible with the Sipex SP483 device as well as popular industry standards. The SP3483
features Sipex's BiCMOS process, allowing low power operation without sacrificing
performance. The SP3483 is internally slew rate limited to reduce EMI and can meet the
requirements of RS-485 and RS-422 up to 250kbps.
+3.3V Low Power Slew Rate Limited
Half-Duplex RS-485 Transceiver
SP3483 DS/04 SP3483 Low Power Slew Rate Limited Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation
2
T
MIN
to T
MAX
and V
CC
= +3.3V
5% unless otherwise noted.
PARAMETERS
MIN.
TYP.
MAX.
UNITS
CONDITIONS
DRIVER
DC Characteristics
Differential Output Voltage
GND
V
CC
Volts
Unloaded; R =
;
Figure 1
Differential Output Voltage
2
V
CC
Volts
with load; R = 50
; (RS-422);
Figure 1
Differential Output Voltage
1.5
V
CC
Volts
with load; R = 27
; (RS-485);
Figure 1
Change in Magnitude of Driver
Differential Output Voltage for
Complimentary States
0.2
Volts
R = 27
or R = 50
;
Figure 1
Driver Common-Mode
Output Voltage
3
Volts
R = 27
or R = 50
;
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
10
A
Applies to DE, DI, RE
Driver Short-Circuit Current
V
OUT
= HIGH
250
mA
-7V
V
O
+12V
V
OUT
= LOW
250
mA
-7V
V
O
+12V
DRIVER
AC Characteristics
Maximum Data Rate
250
kbps
RE = V
CC
, DE = V
CC
Driver Input to Output, t
PLH
400
900
1500
ns
Figures 2 and 8
Driver Input to Output, t
PHL
400
900
1500
ns
Figures 2 and 8
Differential Driver Skew
10
ns
t
DO1
- t
DO2
Figures 2 and 9
Driver Rise or Fall Time
700
1000
ns
From 10% to 90%
Figures 3 and
9
Driver Enable to Output High
700
1300
ns
Figures 4 and 10
Driver Enable to Output Low
690
1300
ns
Figures 5 and 10
Driver Disable Time from Low
80
120
ns
Figures 5 and 10
Driver Disable Time from High
90
120
ns
Figures 4 and 10
RECEIVER
DC Characteristics
Differential Input Threshold
-0.2
+0.2
Volts
-7V
V
CM
+12V
Input Hysteresis
20
mV
V
CM
= 0V
Output Voltage High
V
CC
-0.4
Volts
V
ID
= +200mV, -1.5mA
Output Voltage Low
0.4
Volts
V
ID
= -200mV, 2.5mA
Three-State (High Impedance)
Output Current
+1
A
0V
V
O
V
CC
; RE = V
CC
Input Resistance
12
15
k
-7V
V
CM
+12V
Input Current (A, B); V
IN
= 12V
1.0
mA
DE = 0V, V
CC
= 0V or 3.6V, V
IN
= 12V
Input Current (A, B); V
IN
= -7V
-0.8
mA
DE = 0V, V
CC
= 0V or 3.6V, V
IN
= -7V
Short-Circuit Current
7
60
mA
0V
V
CM
V
CC
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 specifications below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may affect reliability.
V
CC
............................................................................................................+7V
Input Voltages
Logic........................................................-0.3V to (V
CC
+0.5V)
Drivers..................................................-0.3V to (V
CC
+0.5V)
Receivers.................................................................
15V
Output Voltages
Logic........................................................-0.3V to (V
CC
+0.5V)
Drivers......................................................................
15V
Receivers............................................-0.3V to (V
CC
+0.5V)
Storage Temperature.......................................................-65C to +150C
Power Dissipation per package
8-pin NSOIC (derate 6.14mW/C above +70C).........................500mW
8-pin PDIP (derate 11.8mW/C above +70C)..........................1000mW
SPECIFICATIONS
3
SP3483 DS/04 SP3483 Low Power Slew Rate Limited Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation
T
MIN
to T
MAX
and V
CC
= +3.3V
5% unless otherwise noted.
PARAMETERS
MIN.
TYP.
MAX.
UNITS
CONDITIONS
RECEIVER
AC Characteristics
Maximum Data Rate
250
kbps
RE = 0V, DE = 0V
Receiver Input to Output, t
PLH
35
70
120
ns
Figures 6 and 11
Receiver Input to Output, t
PHL
35
70
120
ns
Figures 6 and 11
Differential Receiver Skew
50
ns
t
RSKEW
=
t
RPHL
-
t
RPLH
Figures 6 and 11
Receiver Enable to
Output Low
45
70
ns
Figures 7 and 12; S
1
closed, S
2
open
Receiver Enable to
Output High
45
70
ns
Figures 7 and 12; S
2
closed, S
1
open
Receiver Disable from Low
45
70
ns
Figures 7 and 12; S
1
closed, S
2
open
Receiver Disable from High
45
70
ns
Figures 7 and 12; S
2
closed, S
1
open
Shutdown Timing
Time to Shutdown
50
200
600
ns
RE = 5V, DE = 0V
Driver Enable from Shutdown
to Output High
2000
ns
Figures 4 and 10
Driver Enable from Shutdown
to Output Low
2000
ns
Figures 5 and 10
Receiver Enable from
Shutdown to Output High
2500
ns
Figures 7 and 12; S
2
closed, S
1
open
Receiver Enable from
Shutdown to Output Low
2500
ns
Figures 7 and 12; S
1
closed, S
2
open
POWER REQUIREMENTS
Supply Current
No Load
350
650
A
RE, DI = 0V or V
CC
; DE = V
CC
250
A
RE = 0V, DI = 0V or V
CC
; DE = 0V
Shutdown Mode
10
A
DE = 0V, RE=V
CC
SPECIFICATIONS (continued)
SP3483 DS/04 SP3483 Low Power Slew Rate Limited Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation
4
PIN FUNCTION
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 +3.00V < V
CC
< +3.60V
DESCRIPTION
The SP3483 device is part of a family of +3.3V
low power half-duplex transceivers that meet the
specifications of the RS-485 and RS-422 serial
protocols. The device is pin-to-pin compatible
with the Sipex SP483 device as well as popular
industry standards. The SP3483 features Sipex's
BiCMOS process allowing low power operation
without sacrificing performance.
Drivers
The driver outputs of the SP3483 are differential
outputs meeting the RS-485 and RS-422
standards. The typical voltage output swing
with no load will be 0 Volts to +3.3 Volts.
With a loading of 54
across the differential
outputs, the drivers 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 DE (pin 3) will
force the driver outputs into high impedance
(high-Z).
The SP3483 has internally slew rate limited
driver outputs to minimize EMI. The tranceivers
will operate up to 250kbps. The 250mA I
SC
maximum limit on the driver output allows the
SP3483 to withstand an infinite short circuit
over the -7.0V to +12.0V common mode range
without catastrophic damage to the IC.
SP3483
Pinout (Top View)
RO 1
RE 2
DE 3
DI 4
8 V
CC
7 B
6 A
5 GND
D
R
SP485
Top View
Receivers
The SP3483 receiver has differential inputs with
an input sensitivity as low as
200mV. Input
impedance of the receivers is typically 15k
(12k
minimum). A wide common mode range
of -7V to +12V allows for large ground potential
differences between systems. The receiver of
the SP3483 has a high impedance (high-z)
enable 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 receiver of the SP3483 will operate up to
250kbps. The receiver is equipped with a
fail-safe feature that guarantees the receiver
output will be in a HIGH state when the input
is left unconnected.
Shutdown Mode
The SP3483 is equipped with a Shutdown mode.
To enable the Shutdown state, both the driver
and receiver must be disabled simultaneously.
A logic LOW on DE (pin 3) and a logic HIGH on
RE (pin 2) will put the SP3483 into Shutdown
mode. In Shutdown, supply current will drop to
typical 1
A, 10
A maximum.
5
SP3483 DS/04 SP3483 Low Power Slew Rate Limited Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation
INPUTS
OUTPUTS
LINE
RE
DE
DI CONDITION
B
A
X
1
1
No Fault
0
1
X
1
0
No Fault
1
0
X
0
X
X
Z
Z
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 1. Transmit Function Truth Table
Table 2. Receive Function Truth Table
Figure 2. Driver Propagation Delay Test Circuit
Figure 4. Driver Enable and Disable Timing Circuit,
Output HIGH
Figure 1. Driver DC Test Load Circuit
Figure 6. Receiver Propagation Delay Test Circuit
Figure 7. Receiver Enable and Disable Timing Circuit
R
R
V
OC
D
V
CC
V
OD
GENERATOR
(NOTE 1)
50
V
CC
S1
V
DM
R
L
= 27
OUT
C
L
= 15pF
(NOTE 2)
V
OM
= 1.5V
V
OH
+ V
OL
2
D
GENERATOR
(NOTE 1)
50
S1
R
L
= 110
OUT
C
L
= 50pF
(NOTE 2)
V
OM
= 1.5V
V
OH
+ V
OL
2
D
GENERATOR
(NOTE 1)
50
S1
R
L
= 110
OUT
C
L
= 50pF
(NOTE 2)
D
0V OR 3V
V
CC
GENERATOR
(NOTE 1)
50
1.5V
0V
V
ID
R
OUT
C
L
= 15pF
(NOTE 2)
V
OM
= V
CC
2
1.5V
-1.5V
S3
V
ID
GENERATOR
(NOTE 1)
50
C
L
= 15pF
(NOTE 2)
R
1k
S1
S2
V
CC
Figure 5. Driver Enable and Disable Timing Circuit,
Output LOW
GENERATOR
(NOTE 1)
50
C
L
OUT
D
V
CC
R
L
=
60
C
L
= 15pF (NOTE 2)
Figure 3. Driver Differential Output Delay and Transition
Time Circuit
SP3483 DS/04 SP3483 Low Power Slew Rate Limited Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation
6
Figure 8. Driver Propagation Delay Waveforms
Figure 12. Receiver Enable and Disable Waveforms
Figure 11. Receiver Propagation Delay Waveforms
Figure 10. Driver Enable and Disable Timing Waveforms
0V
V
OH
t
PLH
t
PHL
V
OM
t
PHL
t
PLH
3V
V
OL
V
OH
1.5V
1.5V
INPUT
Y OUTPUT
V
OM
Z OUTPUT
V
OL
V
OM
V
OM
V
OM
= V
OH
+ V
OL
2
1.5V
0V
V
OH
t
PZH
0.25V
t
PHZ
V
OM
t
PZL
t
PLZ
3V
V
OL
V
CC
1.5V
1.5V
DE
OUTPUT
HIGH
V
OM
0.25V
0V
OUTPUT
LOW
V
OM
= V
OH
+ V
OL
2
1.5V
3V
0V
V
CC
t
RPLH
1.5V
t
RPHL
V
OM
V
OM
0V
1.5V
INPUT
OUTPUT
V
OM
= V
CC
2
NOTE 1: The input pulse is supplied by a generator with the following characteristics:
PRR=250KHz, 50% duty cycle, t
r
< 6.0ns, Z
0
=50
.
NOTE 2: C
L
includes probe and stray capacitance.
IN
1.5V
t
DO1
1.5V
t
DO2
3V
0V
OUT
50%
50%
10%
10%
90%
90%
t
TD
t
TD
2.0V
-2.0V
Figure 9. Driver Differential Output Delay and Transition
Time Waveforms
3V
0V
t
PRHZ
1.5V
t
PRZH
t
PRSH
1.5V
1.5V
10%
0V
V
OH
RE
OUTPUT
S1 is open
S2 is closed
S3 = 1.5V
3V
0V
t
PRLZ
1.5V
t
PRZL
t
PRSL
1.5V
1.5V
10%
V
CC
RE
OUTPUT
S1 is closed
S2 is open
S3 = -1.5V
V
OL
7
SP3483 DS/04 SP3483 Low Power Slew Rate Limited Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation
D
ALTERNATE
END PINS
(BOTH ENDS)
D1 = 0.005" min.
(0.127 min.)
E
PACKAGE: PLASTIC
DUALINLINE
(NARROW)
DIMENSIONS (Inches)
Minimum/Maximum
(mm)
A = 0.210" max.
(5.334 max).
E1
C
L
A2
A1 = 0.015" min.
(0.381min.)
B
B1
e = 0.100 BSC
(2.540 BSC)
e
A
= 0.300 BSC
(7.620 BSC)
A2
B
B1
C
D
E
E1
L
0.115/0.195
(2.921/4.953)
0.014/0.022
(0.356/0.559)
0.045/0.070
(1.143/1.778)
0.008/0.014
(0.203/0.356)
0.355/0.400
(9.017/10.160)
0.300/0.325
(7.620/8.255)
0.240/0.280
(6.096/7.112)
0.115/0.150
(2.921/3.810)
0/ 15
(0/15)
8PIN
SP3483 DS/04 SP3483 Low Power Slew Rate Limited Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation
8
D
E
H
PACKAGE: PLASTIC
SMALL OUTLINE (SOIC)
(NARROW)
DIMENSIONS (Inches)
Minimum/Maximum
(mm)
8PIN
A
A1
L
B
e
h x 45
A
A1
B
D
E
e
H
h
L
0.053/0.069
(1.346/1.748)
0.004/0.010
(0.102/0.249
0.014/0.019
(0.35/0.49)
0.189/0.197
(4.80/5.00)
0.150/0.157
(3.802/3.988)
0.050 BSC
(1.270 BSC)
0.228/0.244
(5.801/6.198)
0.010/0.020
(0.254/0.498)
0.016/0.050
(0.406/1.270)
0/8
(0/8)
9
SP3483 DS/04 SP3483 Low Power Slew Rate Limited Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation
ORDERING INFORMATION
Model
Temperature Range
Package
SP3483CN .................................................................................... 0C to +70C ............................................................................ 8-pin Narrow SOIC
SP3483CP .................................................................................... 0C to +70C ................................................................................ 8-pin Plastic DIP
SP3483EN .................................................................................. .-40C to +85C .......................................................................... 8-pin Narrow SOIC
SP3483EP ................................................................................... -40C to +85C .............................................................................. 8-pin Plastic DIP
Please consult the factory for pricing and availability on a Tape-On-Reel option.
Corporation
SIGNAL PROCESSING EXCELLENCE
Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the
application or use of any product or circuit described hereing; neither does it convey any license under its patent rights nor the rights of others.
Sipex Corporation
Headquarters and
Sales Office
22 Linnell Circle
Billerica, MA 01821
TEL: (978) 667-8700
FAX: (978) 670-9001
e-mail: sales@sipex.com
Sales Office
233 South Hillview Drive
Milpitas, CA 95035
TEL: (408) 934-7500
FAX: (408) 935-7600
PDF 
ZIP