1
SP483EDS/05
SP483E Low EMI Half-Duplex RS485 Transceiver
Copyright 2000 Sipex Corporation
SP483E
s
+5V Only
s
Low Power BiCMOS
s
Driver/Receiver Enable for Multi-Drop
configurations
s
Enhanced ESD Specifications:
+15KV Human Body Model
+15KV IEC1000-4-2 Air Discharge
+8KV IEC1000-4-2 Contact Discharge
s
Low EMI Transceiver limited to 250kbps
Enhanced Low EMI Half-Duplex
RS-485 Transceiver
R
D
RO 1
RE 2
DE 3
DI 4
8 Vcc
7 B
6 A
5 GND
SP483E
DESCRIPTION
The SP483E is a half-duplex transceiver that meets the specifications of RS-485 and RS-422
serial protocols with enhanced ESD performance. The ESD tolerance has been improved on
this device to over
15kV for both Human Body Model and IEC1000-4-2 Air Discharge
Method. This device is pin-to-pin compatible with Sipex's SP483 device as well as popular
industry standards. As with the original version, the SP483E features Sipex's BiCMOS
design allowing low power operation without sacrificing performance. The SP483E meet the
requirements of the RS-485 and RS-422 protocols up to 250kbps under load. 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.
SP483EDS/05
SP483E Low EMI Half-Duplex RS485 Transceiver
Copyright 2000 Sipex Corporation
2
SPECIFICATIONS
T
MIN
to T
MAX
and V
CC
= 5V
5% unless otherwise noted.
PARAMETERS
MIN.
TYP.
MAX.
UNITS
CONDITIONS
SP483E DRIVER
DC Characteristics
Differential Output Voltage
GND
V
CC
Volts
Unloaded; R =
;
see Figure 1
Differential Output Voltage
2
V
CC
Volts
with load; R = 50
; (RS-422);
see Figure 1
Differential Output Voltage
1.5
V
CC
Volts
with load; R = 27
; (RS-485);
see Figure 1
Change in Magnitude of Driver
Differential Output Voltage for
Complimentary States
0.2
Volts
R = 27
or R = 50
;
see Figure 1
Driver Common-Mode
Output Voltage
3
Volts
R = 27
or R = 50
;
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
Applies to DE, DI, RE
Driver Input
10
A DI
Control Lines
1
A DE, RE
Driver Short-Circuit Current
V
OUT
= HIGH
250
mA
-7V
V
O
+12V
V
OUT
= LOW
250
mA
-7V
V
O
+12V
SP483E DRIVER
AC Characteristics
Maximum Data Rate
250
Kbps
RE = 5V, DE = 5V; R
DIFF
= 54
,
C
L1
= C
L2
= 100pF
Driver Input to Output
250
800
2000
ns
t
PLH
; R
DIFF
= 54
, C
L1
= C
L2
= 100pF;
see Figures 3 and 5
Driver Input to Output
250
800
2000
ns
t
PHL
; R
DIFF
= 54
, C
L1
= C
L2
= 100pF;
see Figures 3 and 5
Driver Skew
100
800
ns
see Figures 3 and 5,
t
SKEW
= | t
DPLH
- t
DPHL
|
Driver Rise or Fall Time
250
2000
ns
From 10% to 90%; R
DIFF
= 54
,
C
L1
= C
L2
= 100pF;
see Figures 3 and 6
Driver Enable to Output High
250
2000
ns
C
L
= 100pF;
see Figures 4 & 6; S
2
closed
Driver Enable to Output Low
250
2000
ns
C
L
= 100pF;
see Figures 4 & 6; S
1
closed
Driver Disable Time from Low
300
3000
ns
C
L
= 15pF;
see Figures 2 & 8; S
1
closed
Driver Disable Time from High
300
3000
ns
C
L
= 15pF;
see Figures 2 & 8; S
2
closed
SP481E/SP485E 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
3.5
Volts
I
O
= -4mA, V
ID
= +200mV
Output Voltage Low
0.4
Volts
I
O
= +4mA, V
ID
= -200mV
Three-State (High Impedance)
Output Current
1
A
0.4V
V
O
2.4V; RE = 5V
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 5.25V, V
IN
= 12V
Input Current (A, B); V
IN
= -7V
-0.8
mA
DE = 0V, V
CC
= 0V or 5.25V, V
IN
= -7V
Short-Circuit Current
7
95
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...........................................................................500mW
3
SP483EDS/05
SP483E Low EMI Half-Duplex RS485 Transceiver
Copyright 2000 Sipex Corporation
SPECIFICATIONS (continued)
T
MIN
to T
MAX
and V
CC
= 5V
5% unless otherwise noted.
PARAMETERS
MIN.
TYP.
MAX.
UNITS
CONDITIONS
SP483E RECEIVER
AC Characteristics
Maximum Data Rate
250
Kbps
RE = 0V, DE = 0V
Receiver Input to Output
250
2000
ns
t
PLH
; R
DIFF
= 54
,
C
L1
= C
L2
=
100pF;
Figures 3 & 7
Receiver Input to Output
250
2000
ns
t
PHL
; R
DIFF
= 54
,
C
L1
= C
L2
=
100pF;
Figures 3 & 7
Diff. Receiver Skew It
PLH
-t
PHL
I
100
ns
R
DIFF
= 54
; C
L1
= C
L2
= 100pF;
Figures 3 & 7
Receiver Enable to
Output Low
45
70
ns
C
RL
= 15pF;
Figures 2 & 8; S
1
closed
Receiver Enable to
Output High
45
70
ns
C
RL
= 15pF;
Figures 2 & 8; S
2
closed
Receiver Disable from Low
45
70
ns
C
RL
= 15pF;
Figures 2 & 8; S
1
closed
Receiver Disable from High
45
70
ns
C
RL
= 15pF;
Figures 2 & 8; S
2
closed
SP483E
Shutdown Timing
Time to Shutdown
50
200
600
ns
RE = 5V, DE = 0V
Driver Enable from Shutdown
to Output High
2000
ns
C
L
= 100pF;
See Figures 4 & 6; S
2
closed
Driver Enable from Shutdown
to Output Low
2000
ns
C
L
= 100pF;
See Figures 4 & 6; S
1
closed
Receiver Enable from
Shutdown to Output High
300
2500
ns
C
L
= 15pF;
See Figures 2 & 8; S
2
closed
Receiver Enable from
Shutdown to Output Low
300
2500
ns
C
L
= 15pF;
See Figures 2 & 8; S
1
closed
POWER REQUIREMENTS
Supply Voltage
+4.75
+5.25
Volts
Supply Current
SP483E
No Load
900
A
RE = 0V, DI = 0V or V
CC
; DE = V
CC
600
A
RE = 0V, DI = 0V or 5V; DE = 0V
SP483E
Shutdown Mode
10
A
DE = 0V, RE=V
CC
ENVIRONMENTAL AND
MECHANICAL
Operating Temperature
Commercial (_C_)
0
+70
C
Industrial (_E_)
-40
+85
C
Storage Temperature
-65
+150
C
Package
Plastic DIP (_P)
NSOIC (_N)
SP483EDS/05
SP483E Low EMI Half-Duplex RS485 Transceiver
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 4.75V<Vcc< 5.25V.
SP483E
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
Figure 5. Driver Propagation Delays
A
V
OD
V
OC
B
R
R
Figure 1. RS-485 Driver DC Test Load Circuit
Figure 2. Receiver Timing Test Load Circuit
Figure 3. RS-485 Driver/Receiver Timing Test Circuit
Figure 4. RS-485 Driver Timing Test Load #2 Circuit
C
RL
1k
S
2
S
1
V
CC
1k
Test Point
Receiver
Output
B
A
DI
B
A
C
L1
C
L2
R
DIFF
RO
15pF
S
2
S
1
V
CC
C
L
500
Output
Under
Test
+3V
0V
DI
B
A
DRIVER
OUTPUT
V
O
+
DIFFERENTIAL
OUTPUT
V
A
V
B
0V
V
O
1.5V
1.5V
t
PLH
t
R
t
F
f = 100kHz; t
R
< 10ns; t
F
< 10ns
V
O
1/2V
O
1/2V
O
t
PHL
t
DPLH
t
DPHL
t
SKEW =
|
t
DPLH -
t
DPHL
|
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SP483EDS/05
SP483E Low EMI Half-Duplex RS485 Transceiver
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
X
1
X
Fault
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
+3V
0V
DE
5V
V
OL
A, B
0V
1.5V
1.5V
t
ZL
t
ZH
f = 100kHz; t
R
< 10ns; t
F
< 10ns
V
OH
A, B
2.3V
2.3V
t
LZ
t
HZ
0.5V
0.5V
Output normally LOW
Output normally HIGH
+3V
0V
RE
5V
R
0V
1.5V
1.5V
t
ZL
t
ZH
f = 100kHz; t
R
< 10ns; t
F
< 10ns
R
1.5V
1.5V
t
LZ
t
HZ
0.5V
0.5V
Output normally LOW
Output normally HIGH
V
IL
V
IH
Figure 8. Receiver Enable and Disable Times
Figure 7. Receiver Propagation Delays
Figure 6. Driver Enable and Disable Times
V
OH
V
OL
R
1.5V
1.5V
t
PHL
f = 100kHz; t
R
< 10ns; t
F
< 10ns
OUTPUT
V
0D2
+
V
0D2
A B
0V
0V
t
PLH
INPUT
t
SKEW =
|
t
PHL -
t
PLH
|
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