SP490E / SP491E
Enhanced Full-Duplex RS-485 Transceivers
Description
The SP490E is a low power differential line driver/receiver meeting
RS-485 and RS-422 standards up to 10Mbps. The SP491E is identical
to the SP490E with the addition of driver and receiver tri-state enable
lines. Both products feature ±200mV receiver input sensitivity, over
wide common mode range. The SP490E is available in 8-pin NSOIC
packages for operation over the commercial and industrial temperature
ranges. The SP491E is available in 14-pin NSOIC packages for
operation over the commercial and industrial temperature ranges.
FEATURES
■■
5V only
■■
Low power BiCMOS
■■
Driver/receiver enable (SP491E)
■■
RS-485 and RS-422 drivers/receivers
■■
Pin compatible with LTC490 and SN75179
(SP490E)
■■
Pin compatible with LTC491 and SN75180
(SP491E)
■■
Improved ESD specifications:
±15kV Human Body Model
±15kV IEC61000-4-2 Air Discharge
Ordering Information -
Back Page
Block Diagrams
V
CC
R
1
2
R
8 A
7 B
6
D
Z
NC
R
1
2
R
3
RE
DE 4
5
D
6
GND
7
GND
D
14 V
CC
13 NC
12 A
11 B
10
Z
D
GND
3
4
5 Y
9 Y
8
NC
SP490E
SP491E
REV 1.0.2
1/13
SP490E / SP491E
Absolute Maximum Ratings (SP490E)
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
................................................................... .......... ..7.0V
Input Voltages
Drivers......................-0.5V to (V
CC
+ 0.5V)
Receivers...........................................±14V
Output Voltages
Drivers................................................±14V
Receivers..................-0.5V to (V
CC
+ 0.5V)
Storage Temperature.................................-65˚C to +150˚C
Power Dissipation..................................................1000mW
Electrical Characteristics
T
AMB
= T
MIN
to T
MAX
and V
CC
= 5V ±5% unless otherwise noted.
PARAMETERS
SP490E Driver DC Characteristics
Differential output voltage
Differential output voltage
Differential output voltage
Change in magnitude of driver
differential output voltage for
complimentary states
Driver common-mode output voltage
Input high voltage
Input low voltage
Input current
Driver short circuit current
V
OUT
= HIGH
Driver short circuit current
V
OUT
= LOW
SP490E Driver AC Characteristics
Maximum data rate
Driver input to output, t
PLH
Driver input to output, t
PHL
Driver skew
Driver rise or fall time
10
30
30
5
15
40
60
60
Mbps
ns
ns
ns
ns
R
DIFF
= 54Ω, C
L1
= C
L2
= 100pF; Figures 3 & 5
R
DIFF
= 54Ω, C
L1
= C
L2
= 100pF; Figures 3 & 5
t
SKEW
= | t
DPLH
- t
DPHL
|;
Figures 3 & 5
From 10%-90%;
R
DIFF
= 54Ω,
C
L1
= C
L2
= 100pF; Figures 3 & 5
2.0
0.8
±10
±250
±250
2
1.5
V
CC
V
CC
V
CC
0.2
3
V
V
V
V
V
V
V
µA
mA
mA
Unloaded; R = ∞Ω; Figure 1
With load; R = 50Ω (RS-422); Figure 1
With load; R = 27Ω (RS-485); Figure 1
R = 27Ω or R = 50Ω; Figure 1
R = 27Ω or R = 50Ω; Figure 1
Applies to D
Applies to D
Applies to D
-7V ≤ V
O
≤ 12V
-7V ≤ V
O
≤ 12V
MIN.
TYP.
MAX.
UNITS
CONDITIONS
REV 1.0.2
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SP490E / SP491E
Electrical Characteristics (Continued)
T
AMB
= T
MIN
to T
MAX
and V
CC
= 5V ±5% unless otherwise noted.
PARAMETERS
SP490E Receiver DC Characteristics
Differential input threshold
Input hysteresis
Output voltage HIGH
Output voltage LOW
Input resistance
Input current (A, B); V
IN
= 12V
Input current (A, B); V
IN
= -7V
Short circuit current
SP490E Receiver AC Characteristics
Maximum data rate
Receiver input to output, t
PLH
Receiver input to output, t
PHL
Differential receiver skew, |t
PLH
- t
PHL
|
Power Requirements
Supply Voltage
Supply Current
SP490E Environmental and Mechanical
Operating Temperture
Commercial (_C_)
Industrial (_E_)
Storage Temperature
Package
NSOIC (_N)
0
-40
-65
70
85
150
°C
°C
°C
4.75
900
5.25
V
µA
10
20
20
45
45
13
100
100
Mbps
ns
ns
ns
R
DIFF
= 54Ω, C
L1
= C
L2
= 100pF;
Figures 3 and 7
R
DIFF
= 54Ω, C
L1
= C
L2
= 100pF;
Figures 3 and 7
R
DIFF
= 54Ω, C
L1
= C
L2
= 100pF;
Figures 3 and 7
12
15
±1.0
-0.8
85
3.5
0.4
-0.2
70
0.2
Volts
mV
Volts
Volts
kΩ
mA
mA
mA
-7V ≤ V
CM
≤ 12V
V
CM
= 0V
V
ID
= 200mV, I
O
= -4mA
V
ID
= -200mV, I
O
= 4mA
-7V ≤ V
CM
≤ 12V
V
IN
= 12V
V
IN
= -7V
0V ≤ V
O
≤ V
CC
MIN.
TYP.
MAX.
UNITS
CONDITIONS
REV 1.0.2
3/13
SP490E / SP491E
Test Circuits
A
R
V
OD
R
B
V
OC
Receiver
Output
C
RL
Test Point
S
1
1kΩ
S
2
1kΩ
V
CC
Figure 1: Driver DC Test Load Circuit
Figure 2: Receiver Timing Test Load Circuit
3V
DE
DI
D
R
DIFF
C
L2
C
L1
R
RO
15pF
Output
Under
Test
500Ω
C
L
S
1
V
CC
S
2
Figure 3: Driver/Receiver Timing Test Circuit
Figure 4: Driver Timing Test Load #2 Circuit
REV 1.0.2
4/13
SP490E / SP491E
Switching Waveforms
f = 1MHz; t
R
≤ 10ns; t
F
≤ 10ns
1.5V
t
PLH
V
O
1/2V
O
t
DPLH
t
DPHL
t
PHL
1/2V
O
1.5V
DI
+3V
0V
Z
Y
V
O
+
0V
V
O
–
DRIVER
OUTPUT
V
DIFF
V
Z
– V
Y
t
R
t
F
t
SKEW
= |t
DPLH
- t
DPHL
|
Figure 5: Driver Propagation Delays
f = 1MHz; t
R
≤ 10ns; t
F
≤ 10ns
DE
3V
0V
1.5V
t
ZL
2.3V
Output normally LOW
Output normally HIGH
1.5V
t
LZ
0.5V
0.5V
t
HZ
Y, Z
V
OL
V
OH
Y, Z
0V
2.3V
t
ZH
Figure 6: Driver Enable and Disable Times
A– B
V
OD2
+
V
OD2
–
V
OH
V
OL
t
PHL
f = 1MHz; t
R
≤ 10ns ; t
F
≤ 10ns
0V
INPUT
0V
R
1.5V
OUTPUT
t
PLH
1.5V
t
SKEW
= |t
DPLH
- t
DPHL
|
Figure 7: Receiver Propagation Delays
REV 1.0.2
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