SIPEX SP485REN

SP481R/SP485R
®
1/10th Unit Load RS-485 Transceiver
FEATURES
■ Allows Over 400 Transceivers On A
Transmission Line (1/10th Unit Load)
■ High Impedance on Receiver Inputs
(RIN = 150kΩ typical)
■ Half-Duplex Configuration Consistent
With Industry Standard Pinout
■ –7V to +12V Common Mode Input
Voltage Range
■ Includes Shutdown Mode (ICC < 10µA)
(For SP481R Only)
■ Low Power Consumption (250mW)
■ Separate Driver and Receiver Enable
Now Available in Lead Free Packaging
DESCRIPTION
The SP481R and SP485R are pin-to-pin equivalent with our existing SP485 product and contain
enhancements such as higher ESD tolerance and high receiver input impedance. The higher
receiver input impedance allows for connecting over 400 transceivers on a single transmission
line without degrading the RS-485 driver signal. Each device is packaged in an 8-pin plastic DIP
or 8-pin narrow SOIC package. The SP481R offers a shutdown feature via the enable pins which
will reduce the supply current (ICC) below 0.5µA typical.
TYPICAL APPLICATION CIRCUIT
R
8
VCC
RE 2
7
B
DE 3
6
A
5
GND
RO 1
D
DI 4
SP485
Top View
Date: 6/21/04
SP485R RS-485 Serial Transceiver
1
© Copyright 2004 Sipex Corporation
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.
VCC...........................................................................+7V
Storage Temperature..........................-65˚C to +150˚C
Power Dissipation
8-pin Plastic DIP...........................1000mW
8-pin Plastic N-SOIC.......................1000mW
Package Derating:
8-pin Plastic DIP
øJA....................................................62 °C/W
8-pin Plastic N-SOIC
øJA....................................................62 °C/W
ELECTRICAL CHARACTERISTICS
Typically 25°C @ Vcc = +5V unless otherwise noted.
MIN.
LOGIC INPUTS
VIL
VIH
LOGIC OUTPUTS
VOL
VOH
RS-485 DRIVER
DC Characteristics
TTL Input Levels
VIL
VIH
Outputs
Open Circuit Voltage
Differential Output
Balance
Common-Mode Output
Output Current
Short Circuit Current
AC Characteristics
Maximum Data Rate
Output Transition Time
Propagation Delay
tPHL
tPLH
Driver Output Skew
RS-485 RECEIVER
DC Characteristics
TTL Output Levels
VOL
VOH
Tri-State Output Current
Inputs
Common Mode Range
Receiver Sensitivity
Input Impedance
Date: 6/21/04
TYP.
MAX.
0.8
Volts
Volts
0.4
Volts
Volts
0.8
Volts
Volts
6.0
5.0
±0.2
3.0
Volts
Volts
Volts
Volts
mA
mA
2.0
2.4
2.0
1.5
28.0
±250
5
Mbps
ns
30
60
60
5
IOUT= -3.2mA
IOUT= 1.0mA
RL=54Ω, CL=50pF
|VT| - |VT|
RL=54Ω
Terminated in –7V to +12V
RL=54Ω
Rise/fall time, 10%–90%
See Figures 3 and 5
RDIFF=54Ω, CL1=CL2=100pF
RDIFF=54Ω, CL1=CL2=100pF
see Figure 3 and 5,
tSKEW = | tDPLH - tDPHL |
ns
ns
ns
0.4
Volts
Volts
µA
0.4V≤VOUT ≤2.4V; RE = VCC
Volts
Volts
kΩ
–7V ≤ VCM ≤ +12V
–7V ≤ VCM ≤ +12V
±1
120
CONDITIONS
100
100
15
2.4
–7.0
UNITS
+12.0
±0.2
150
SP485R RS-485 Serial Transceiver
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© Copyright 2004 Sipex Corporation
ELECTRICAL CHARACTERISTICS
Typically 25°C @ Vcc = +5V unless otherwise noted.
MIN.
AC Characteristics
Maximum Data Rate
Propagation Delay
tPHL
tPLH
Differential Receiver Skew
ENVIRONMENTAL
Operating Temperature
Commercial (..C..)
Industrial (..E..)
Storage Temperature
MAX.
1
UNITS
CONDITIONS
Mbps
1200
1200
ns
ns
ns
See Figures 3 and 7
RDIFF=54Ω, CL1=CL2=100pF
RDIFF=54Ω, CL1=CL2=100pF
| tPLH – tPHL |; RDIFF=54Ω,
CL1=CL2=100pF, see Figures 3 and 7
600
ns
RE = VCC, DE = 0V
40
40
500
500
ns
ns
40
40
500
500
ns
ns
40
40
500
500
ns
ns
40
40
500
500
ns
ns
60
SHUTDOWN TIMING (SP481R)
Time to Shutdown
50
RS-485 Driver
Enable Time
Enable to Low
Enable to High
Disable Time
Disable From Low
Disable From High
RS-485 Receiver
Enable Time
Enable to Low
Enable to High
Disable Time
Disable From Low
Disable From High
POWER REQUIREMENTS
Supply Voltage VCC
Supply Current ICC
No Load
No Load
Supply Current in Shutdown
TYP.
+4.75
+5.25
300
500
0.5
0
–40
–65
See Figures 4 and 6
CL=15pF, S1 Closed
CL=15pF, S2 Closed
See Figures 4 and 6
CL=15pF, S1 Closed
CL=15pF, S2 Closed
See Figures 2 and 8
CL=15pF, S1 Closed
CL=15pF, S2 Closed
See Figures 2 and 8
CL=15pF, S1 Closed
CL=15pF, S2 Closed
Volts
500
900
10
µA
µA
µA
+70
+85
+150
°C
°C
°C
RE = VCC or 0V, DE = 0V
RE = VCC or 0V, DE = VCC
RE = VCC, DE = OV
RECEIVER INPUT GRAPH
SP485R Reciever
Standard SP485R Reciever
+100µA
+1.0mA
-7V
-7V
-3V
+6V
+6V
+12V
+12V
-60µA
-0.6 mA
1/10 Unit Load
Maximum Input Current
versus voltage.
(Shaded region)
1 Unit Load
Maximum Input Current
versus voltage.
(Shaded region)
Date: 6/21/04
-3V
SP485R RS-485 Serial Transceiver
3
© Copyright 2004 Sipex Corporation
TEST CIRCUITS
A
VOD
VCC
S1
CRL
R
1kΩ
Test Point
Receiver
Output
R
1kΩ
VOC
S2
B
Figure 1. Driver DC Test Load Circuit
CL1
DI
A
Figure 2. Receiver Timing Test Load Circuit
A
RL
Output
Under
Test
RO
B
B
CL2
15pF
S1
500Ω
VCC
CL
S2
Figure 4. Driver Timing Test Load #2 Circuit
Figure 3. Driver/Receiver Timing Test Circuit
SWITCHING WAVEFORMS
+3V
f = 1MHz; tR < 10ns; tF < 10ns
1.5V
DI
1.5V
0V
DRIVER
OUTPUT
B
tPLH
tPHL
VO 1/2VO
tPLH
1/2VO
A
tDPLH
DIFFERENTIAL VO+
OUTPUT 0V
VA – VB VO–
tDPHL
tR
tF
tSKEW = | tDPLH - tDPHL |
Figure 5. Driver Propagation Delays
Date: 6/21/04
SP485R RS-485 Serial Transceiver
4
© Copyright 2004 Sipex Corporation
f = 1MHz; tR < 10ns; tF < 10ns
+3V
1.5V
DE
0V
1.5V
tZL
tLZ
5V
2.3V
A, B
VOL
VOH
A, B
2.3V
0V
Output normally LOW
0.5V
Output normally HIGH
0.5V
tZH
tHZ
Figure 6. Driver Enable and Disable Times
f = 1MHz; tR < 10ns; tF < 10ns
V0D2+
A–B
0V
VOH
1.5V
RECEIVER OUT
VOL
0V
INPUT
V0D2–
1.5V
OUTPUT
tPHL
tPLH
tSKEW = | tPHL - tPLH |
Figure 7. Receiver Propagation Delays
+3V
RE
0V
1.5V f = 1MHz; t < 10ns; t < 10ns
R
F
tZL
5V
RECEIVER OUT
VIL
1.5V
1.5V
tLZ
Output normally LOW
0.5V
Output normally HIGH
0.5V
VIH
RECEIVER OUT
0V
1.5V
tZH
tHZ
Figure 8. Receiver Enable and Disable Times
Date: 6/21/04
SP485R RS-485 Serial Transceiver
5
© Copyright 2004 Sipex Corporation
GENERAL DESCRIPTION
The SP485R is a low power RS-485 differential
transceiver. Similar to the SP485, the SP485R
contains a half-duplex driver and receiver with
tri-state control. However, the SP485R is intended for increased connections on a single bus
compared to the orignal RS-485 specification.
with the two 125Ω cable termination resistors
on each end.
The receiver contains a enable pin (RE) which
enables the receiver when a logic LOW is
asserted. A logic HIGH will tri-state the
receiver output and the inputs will maintain
at least 120kΩ impedance. The receiver can
operate to at least 1Mbps.
The RS-485 standard is ideal for multi-drop
applications where one bus can contain many
drivers and/or receivers. The RS-485 standard
implementation allows up to 32 transceivers to
be connected on to the data bus. RS-485 is also
specified for driving higher speeds over long
cable lengths of up to 4,000 feet. The SP485R
and SP481R exceed the standard b allowing up
to 400 receivers to share a bus.
The receiver also contains a fail-safe feature
which outputs a logic HIGH when the inputs are
open as in a disconnected cable.
SHUTDOWN MODE
The SP481R includes a shutdown function to
reduce power consumption. The shutdown is
activated by simultaneously applying a logic
LOW to DE and a logic HIGH to RE. While in
the shutdown mode, the power supply current is
typically less than 1µA. The driver outputs are
disabled and are at a high impedance state
determined by the receiver input impedance
which should be at least 120kΩ. The receiver
output is at also at high impedance during
shutdow. Output leakage current when the
receiver is disabled is under 1µA.
DRIVERS
The driver output complies with the RS-485
electrical characteristics as specified by the
standard. The output swings from 0V to VCC and
maintains greater than +1.5V with a 54Ω load
attached between the two outputs. In adhering
to the RS-485 specification, the driver outputs
inherently comply with the RS-422 standard.
With a load of 100Ω between the two outputs,
the driver can sustain at least +2.0V.
The driver contains an enable pin (DE) which
tri-states the output when DE is a logic LOW.
The outputs during the tri-stated condition are
at a high impedance (>100kΩ). A logic HIGH
enables the driver for normal operation. The
driver can operate to at least 5Mbps.
RECEIVERS
The SP485R receiver has differential inputs
with an input sensitivity of lower than ±200mV.
As mentioned above, the RS-485 specification
allows up to 32 transceivers on a the same bus.
The SP485R allows over 400 transceivers on
the same bus due to the high input impedance of
at least 120kΩ. This higher capacity allows
more components to be attached to the same
bus without degrading the signal quality. The
drivers are still able to drive an equivalent 54Ω
from the 320 transceivers with an input
impedance of at least 120kΩ in parallel along
Date: 6/21/04
SP485R RS-485 Serial Transceiver
6
© Copyright 2004 Sipex Corporation
PACKAGE: 8 PIN PDIP
N
E
INDEX
AREA
E1 E
2
1
3
N/2
c
eA
eB
A1
D
A
e
A2
D1
L
b2
b
b3
8 PIN PDIP
JEDEC MS-001
(BA) Variation
A
Dimensions in inches
MIN
-
-
.210
-
-
.115
.130
.195
.014
A1
.015
A2
b
.018
.022
b2
.045
.060
.070
b3
.030
.039
.045
c
.008
.010
.014
D
.355
.365
.400
D1
.005
-
-
E
.300
.310
.325
E1
.240
.250
.280
b
c
8 PIN PDIP
.100 BSC
e
eA
Date: 6/21/04
NOM MAX
.300 BSC
eB
-
-
.430
L
.115
.130
.150
SP485R RS-485 Serial Transceiver
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© Copyright 2004 Sipex Corporation
PACKAGE: 8 PIN NSOIC
D
e
E/2
E1
E
SEE VIEW C
E1/2
1
b
INDEX AREA
(D/2 X E1/2)
Ø1
A
TOP VIEW
Gauge Plane
L2
Seating Plane
Ø1
Ø
L
L1
VIEW C
A2
A
SEATING PLANE
A1
SIDE VIEW
DIMENSIONS
Minimum/Maximum
(mm)
b
WITH PLATING
8 Pin NSOIC
(JEDEC MS-012,
AA - VARIATION)
COMMON HEIGHT DIMENSION
SYMBOL
A
A1
A2
b
c
D
E
E1
e
L
L1
L2
Ø
Ø1
Date: 6/21/04
MIN NOM MAX
1.75
1.35
0.25
0.10 1.25
1.65
0.31
0.51
0.17
0.25
4.90 BSC
6.00 BSC
3.90 BSC
1.27 BSC
0.40 1.27
1.04 REF
0.25 BSC
0º
8º
5º
15º
c
BASE METAL
CONTACT AREA
PACKAGE: 8 PIN NSOIC
SP485R RS-485 Serial Transceiver
8
© Copyright 2004 Sipex Corporation
ORDERING INFORMATION
Part Number
Temperature Range
Package Types
SP481RCP ........................................................................ 0°C to +70°C ................................................................................................ 8 Pin PDIP
SP481RCN ........................................................................ 0°C to +70°C ............................................................................................. 8 Pin NSOIC
SP481RCN/TR .................................................................. 0°C to +70°C ............................................................................................. 8 Pin NSOIC
SP481REP ..................................................................... -40°C to +85°C ................................................................................................ 8 Pin PDIP
SP481REN ..................................................................... -40°C to +85°C ............................................................................................. 8 Pin NSOIC
SP481REN/TR ............................................................... -40°C to +85°C ............................................................................................. 8 Pin NSOIC
SP485RCP ........................................................................ 0°C to +70°C ................................................................................................ 8 Pin PDIP
SP485RCN ........................................................................ 0°C to +70°C ................................................................................................ 8 Pin NOIC
SP485RCN/TR .................................................................. 0°C to +70°C ................................................................................................ 8 Pin NOIC
SP485REP ..................................................................... -40°C to +85°C ................................................................................................ 8 Pin PDIP
SP485REN ..................................................................... -40°C to +85°C ................................................................................................ 8 Pin NOIC
SP485REN/TR ............................................................... -40°C to +85°C ................................................................................................ 8 Pin NOIC
Available in lead free packaging. To order add “-L” suffix to part number.
Example: SP485REN/TR = standard; SP485REN-L/TR = lead free
/TR = Tape and Reel
Pack quantity is 2,500 for NSOIC.
REVISION HISTORY
DATE
6/21/04
REVISION
A
DESCRIPTION
Added extended temp range and tape and reel part numbers. Updated
packaging specs.
Corporation
ANALOG EXCELLENCE
Sipex Corporation
Headquarters and
Sales Office
233 South Hillview Drive
Milpitas, CA 95035
TEL: (408) 934-7500
FAX: (408) 935-7600
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 herein; neither does it convey any license under its patent rights nor the rights of others.
Date: 6/21/04
SP485R RS-485 Serial Transceiver
9
© Copyright 2004 Sipex Corporation