®
SP3486 and SP3487
+3.3V Low Power Quad
RS-485/RS-422 Line Drivers
■
RS-485 or RS-422 Quad Differential
Line Drivers
■
Operates from a single +3.3V supply
■
Interoperable with +5.0V logic
■
Tri-state Output Control
■
-7V to +12V Common-Mode Input
Voltage Range
■
Common Driver Enable Control (SP3486)
■
Independent Driver Enable Controls for
each pair of Drivers (SP3487)
■
Compatibility with LTC486
and SN75172 (SP3486)
■
Compatibility with LTC487
and SN75174 (SP3487)
DESCRIPTION
The
SP3486
and the
SP3487
are +3.3V low power quad drivers that meet the specifications
of the RS-485 and RS-422 serial protocols. These devices are pin-to-pin compatible with
Sipex's SP486 and SP487 devices as well as popular industry standards. The
SP3486
and
SP3487
feature Sipex's BiCMOS process allowing low power operation without sacrificing
performance. The
SP3486
and
SP3487
meet the electrical specifications of RS-485 and
RS-422 serial protocols up to 10Mbps under load. The SP3486 features a common driver
enable control. The
SP3487
provides independent driver enable controls for each pair of
drivers. Both devices feature tri-state outputs and a -7V to +12V common-mode input voltage
range.
DI
1
DO
1
A
DO
1
B
EN
DO
2
B
DO
2
A
DI
2
GND
1
SP3486
1
16
15
V
CC
DI
4
DO
4
A
DO
4
B
EN
DO
3
B
DO
3
A
DI
3
DI
1
DO
1
A
DO
1
B
EN
1
/EN
2
DO
2
B
DO
2
A
DI
2
GND
1
SP3487
1
16
15
V
CC
DI
4
DO
4
A
DO
4
B
EN
3
/EN
4
DO
3
B
DO
3
A
DI
3
2
2
4
3
4
5
6
14
13
12
11
3
4
5
6
4
14
13
12
11
2
7
10
2
7
10
3
8
9
3
8
9
10/15/02
SP3486/3487 Low Power Quad RS485/422 Line Drivers
© Copyright 2002 Sipex Corporation
1
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only and functional operation of the device
at these 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
......................................................................................... +6.0V
Input Voltages
Logic ............................................................ –0.3V to +6.0V
Drivers ......................................................... –0.3V to +6.0V
Driver Output Voltage .............................................................
±14V
Input Currents
Logic ........................................................................
±25mA
Driver .......................................................................
±25mA
Storage Temperature ............................................ –65°C to +150°C
Power Dissipation
Plastic DIP .......................................................................... 375mW
(derate 7mW/°C above +70°C)
Small Outline ...................................................................... 375mW
(derate 7mW/°C above +70°C)
Lead Temperature (soldering, 10 sec) ................................... 300°C
SPECIFICATIONS
V
CC
= 3.3V±5%; typicals at 25°C; T
MIN
≤
T
A
≤
T
MAX
unless otherwise noted.
PARAMETER
DC CHARACTERISTICS
Digital Inputs
Voltage
V
IL
V
IH
Input Current
DRIVER OUTPUTS
Differential Voltage
MIN.
TYP.
MAX.
UNIT
CONDITIONS
DI, EN, EN, EN
1
/EN
2
, EN
3
/EN
4
0.8
2.0
±2
V
CC
V
CC
3
0.2
Volts
Volts
µA
Volts
Volts
Volts
Volts
Volts
Mbps
V
IN
= 0V to V
CC
unloaded
R = 50Ω(RS-422)
R = 27Ω (RS-485);
Figure 1
R = 27Ω or 50Ω;
Figure 1
R = 27Ω or 50Ω;
Figure 1
R = 50Ω (RS-422)
R = 27Ω (RS-485)
-7V
≤V
O
≤
+12V
-7V
≤V
O
≤
+12V
V
O
= -7V to +12V, T
A
=25
o
C
2
1.5
Common Mode Output Voltage
Change in Common Mode Output Magnitude
for Complementary Output State
Maximum Data Rate
10
Short–circuit Current
V
OH
V
OL
High Impedance Output Current
POWER REQUIREMENTS
Supply Voltage
3.00
Supply Current
±250
±250
1
3.30
3.00
0.10
3.60
mA
mA
µA
Volts
µA
µA
No load, output enabled
No load, output disabled
ENVIRONMENTAL AND MECHANICAL
Operating Temperature
–C
0
+70
–E
-40
+85
Storage Temperature
-65
+150
Package
–_P
16–pin Plastic DIP
–_T
16–pin SOIC
°C
°C
°C
10/15/02
SP3486/3487 Low Power Quad RS485/422 Line Drivers
© Copyright 2000 Sipex Corporation
2
PINOUT — SP3486
V
DM
DI
1
DO
1
A
DO
1
B
EN
DO
2
B
DO
2
A
DI
2
GND
1
SP3486
1
16
15
V
CC
R
L
= 27Ω
DI
4
DO
4
A
DO
4
B
EN
DO
3
B
DO
3
A
2
S1
D
GENERATOR
(NOTE 1)
50Ω
V
CC
OUT
C
L
= 15PF
(NOTE 2)
4
3
4
5
6
14
13
12
11
V
OM
= V
OH
+ V
OL
2
1.5V
2
7
10
3
8
9
DI
3
Figure 2. Driver Propagation Delay Test Circuit
Pin 8 — GND — Digital Ground.
Pin 9 — DI
3
— Driver 3 Input — If Driver 3 output
is enabled, logic 0 on DI
3
forces driver output
DO
3
A low and DO
3
B high. A logic 1 on DI
3
with
Driver 3 output enabled forces driver DO
3
A high
and DO
3
B low.
Pin 10 — DO
3
A — Driver 3 output A.
Pin 11 — DO
3
B — Driver 3 output B.
Pin 12 — EN — Driver Output Disable. Please
refer to SP486
Truth Table (1).
S1
D
C
L
= 50pF
(NOTE 2)
GENERATOR
(NOTE 1)
50Ω
OUT
R
L
= 110Ω
SP3486 PINOUT
Pin 1 — DI
1
— Driver 1 Input — If Driver 1 output
is enabled, logic 0 on DI
1
forces driver output
DO
1
A low and DO
1
B high. A logic 1 on DI
1
with
Driver 1 output enabled forces driver DO
1
A high
and DO
1
B low.
Pin 2 — DO
1
A — Driver 1 output A.
Pin 3 — DO
1
B — Driver 1 output B.
Pin 4 — EN — Driver Output Enable. Please refer
to SP3486
Truth Table (1).
Pin 5 — DO
2
B — Driver 2 output B.
Pin 6 — DO
2
A — Driver 2 output A.
Pin 7 — DI
2
— Driver 2 Input — If Driver 2 output
is enabled, logic 0 on DI
2
forces driver output
DO
2
A low and DO
2
B high. A logic 1 on DI
2
with
Driver 2 output enabled forces driver DO
2
A high
and DO
2
B low.
V
OM
= V
OH
+ V
OL
2
1.5V
Figure 3. Driver Enable and Disable Timing Circuit,
Output HIGH
V
CC
R
S1
R
L
= 110Ω
0V OR 3V
D
C
L
= 50pF
(NOTE 2)
OUT
D
V
CC
V
OD
R
V
OC
GENERATOR
(NOTE 1)
50Ω
Figure 1. Driver DC Test Load Circuit
Figure 4. Driver Enable and Disable Timing Circuit,
Output LOW
SP3486/3487 Low Power Quad RS485/422 Line Drivers
© Copyright 2002 Sipex Corporation
10/15/02
3
PINOUT — SP3487
INPUT
DI
1
DO
1
A
DO
1
B
EN
1
/EN
2
DO
2
B
DO
2
A
DI
2
GND
1
ENABLES
EN
H
H
X
X
L
EN
X
X
L
L
H
OUTPUTS
OUTA
H
L
H
L
Hi–Z
OUTB
L
H
L
H
Hi–Z
SP3487
1
16
15
V
CC
DI
4
DO
4
A
DO
4
B
EN
3
/EN
4
DO
3
B
DO
3
A
DI
3
DI
H
L
H
L
X
2
4
3
4
5
6
14
13
12
11
2
7
10
3
8
9
Table 1. SP3486 Truth Table
Pin 8 — GND — Digital Ground.
Pin 9 — DI
3
— Driver 3 Input — If Driver 3 output
is enabled, logic 0 on DI
3
forces driver output
DO
3
A low and DO
3
B high. A logic 1 on DI
3
with
Driver 3 output enabled forces driver DO
3
A high
and DO
3
B low.
Pin 10 — DO
3
A — Driver 3 output A.
Pin 11 — DO
3
B — Driver 3 output B.
Pin 12 — EN
3
/EN
4
— Driver 3 and 4 Output
Enable. Please refer to
SP3487
Truth Table (2).
Pin 13 — DO
4
B — Driver 4 output B.
Pin 14 — DO
4
A — Driver 4 output A.
Pin 15 — DI
4
— Driver 4 Input — If Driver 4
output is enabled, logic 0 on DI
4
forces driver
output DO
4
A low and DO
4
B high. A logic 1 on DI
4
with Driver 4 output enabled forces driver DO
4
A
high and DO
4
B low.
Pin 16 —V
CC
—Positive Supply +3.00V < V
CC
< +3.60V
Pin 13 — DO
4
B — Driver 4 output B.
Pin 14 — DO
4
A — Driver 4 output A.
Pin 15 — DI
4
— Driver 4 Input — If Driver 4
output is enabled, logic 0 on DI
4
forces driver
output DO
4
A low and DO
4
B high. A logic 1 on DI
4
with Driver 4 output enabled forces driver DO
4
A
high and DO
4
B low.
Pin 16—V
CC
—Positive Supply +3.00V<V
CC
<+3.60V
SP3487 PINOUT
Pin 1 — DI
1
— Driver 1 Input — If Driver 1 output
is enabled, logic 0 on DI
1
forces driver output
DO
1
A low and DO
1
B high. A logic 1 on DI
1
with
Driver 1 output enabled forces driver DO
1
A high
and DO
1
B low.
Pin 2 — DO
1
A — Driver 1 output A.
Pin 3 — DO
1
B — Driver 1 output B.
Pin 4 — EN
1
/EN
2
— Driver 1 and 2 Output
Enable. Please refer to SP3487 Truth Table (2).
Pin 5 — DO
2
B — Driver 2 output B.
INPUT
ENABLES
EN1/EN2 or EN3/EN4
H
H
L
OUTPUTS
OUTA
H
L
Hi–Z
OUTB
L
H
Hi–Z
Pin 6 — DO
2
A — Driver 2 output A.
Pin 7 — DI
2
— Driver 2 Input — If Driver 2 output
is enabled, logic 0 on DI
2
forces driver output
DO
2
A low and DO
2
B high. A logic 1 on DI
2
with
Driver 2 output enabled forces driver DO
2
A high
and DO
2
B low.
10/15/02
DI
H
L
X
Table 2. SP3487 Truth Table
© Copyright 2000 Sipex Corporation
SP3486/3487 Low Power Quad RS485/422 Line Drivers
4
FEATURES
The
SP3486
and the
SP3487
are +3.3V low power
quad line drivers that meet the specifications of
the RS-485 and RS-422 serial protocols. These
devices are pin-to-pin compatible with Sipex's
SP486 and SP487 devices as well as popular
industry standards. The
SP3486
and
SP3487
devices feature Sipex's BiCMOS process
allowing low power operation without sacrificing
performance.
The RS-485 standard is ideal for multi-drop
applications or for long distance interfaces.
RS-485 allows up to 32 drivers and 32 receivers
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 accomodate
ground potential differences. Data is virtually
immune to noise in the transmission line because
the RS-485 protocol is a differential interface.
Driver
The drivers for both the
SP3486
and
SP3487
have differential outputs. The typical voltage
output swing with no load will be 0V to +5V.
With worst case loading of 54Ω across the
differential outputs, the driver can maintain
greater than +1.5V voltage levels.
The drivers of the
SP3486
feature active HIGH
and active LOW common driver enable
controls. Refer to
SP3486
Truth Table in Table
1. The
SP3487
provides independent, active
high driver enable controls for each pair of
drivers. Refer to
SP3487
Truth Table in Table 2.
The driver outputs are short-circuit limited
to 250mA. The
SP3486
and
SP3487
drivers
meet the electrical specifications of RS-485
and RS-422 serial protocols up to 10Mbps
under load.
AC PARAMETERS
V
CC
= +3.3V±5%; typicals at 25°C; T
AMB
= 25°C unless otherwise noted.
PARAMETER
PROPAGATION DELAY
Driver Input to Output
MIN.
TYP.
MAX.
UNIT
CONDITIONS
Figure 2 and 5
Low to High (t
PLH
)
High to Low (t
PHL
)
Differential Driver Skew
Driver Rise Time (t
R
)
SP3486
SP3487
Driver Fall Time (t
F
)
SP3486
SP3487
DRIVER ENABLE
To Output High
To Output Low
DRIVER DISABLE
From Output Low
From Output High
20
20
40
40
5
60
60
10
ns
ns
ns
| t
PHL
(Y) - t
PLH
(Y) |, | t
PHL
(Z) - t
PLH
(Z) | ,
Figures 2 and 5
10% to 90% R
DIFF
= 60Ω
90% to 10% R
DIFF
= 60Ω
10
10
10
10
110
110
ns
ns
ns
ns
ns
ns
Figures 3 and 6
Figures 4 and 6
110
110
ns
ns
Figures 4 and 6
Figures 3 and 6
10/15/02
SP3486/3487 Low Power Quad RS485/422 Line Drivers
© Copyright 2002 Sipex Corporation
5