1
FN6046.3
ISL8483, ISL8485, ISL8488,
ISL8489, ISL8490, ISL8491
5V, Low Power, High Speed or Slew Rate
Limited, RS-485/RS-422 Transceivers
The Intersil RS-485/RS-422 devices are BiCMOS 5V
powered, single transceivers that meet both the RS-485 and
RS-422 standards for balanced communication. Unlike
competitive devices, this Intersil family is specified for 10%
tolerance supplies (4.5V to 5.5V).
The ISL8483, ISL8488, and ISL8489 utilize slew rate limited
drivers which reduce EMI, and minimize reflections from
improperly terminated transmission lines, or unterminated
stubs in multidrop and multipoint applications.
Data rates up to 5Mbps are achievable by using the
ISL8485, ISL8490, or ISL8491, which feature higher slew
rates.
All devices present a "single unit load" to the RS-485 bus,
which allows up to 32 transceivers on the network.
Receiver (Rx) inputs feature a "fail-safe if open" design,
which ensures a logic high Rx output if Rx inputs are
floating.
Driver (Tx) outputs are short circuit protected, even for
voltages exceeding the power supply voltage. Additionally,
on-chip thermal shutdown circuitry disables the Tx outputs to
prevent damage if power dissipation becomes excessive.
The ISL8488 - 91 are configured for full duplex (separate Rx
input and Tx output pins) applications. The ISL8488 and
ISL8490 are offered in space saving 8 lead packages for
applications not requiring Rx and Tx output disable functions
(e.g., point-to-point). Half duplex configurations (ISL8483,
ISL8485) multiplex the Rx inputs and Tx outputs to allow
transceivers with Rx and Tx disable functions in 8 lead
packages.
Features
Specified for 10% Tolerance Supplies
Class 3 ESD Protection (HBM) on all Pins. . . . . . . . >7kV
High Data Rates. . . . . . . . . . . . . . . . . . . . . . up to 5Mbps
Slew Rate Limited Versions for Error Free Data
Transmission at 250kbps (ISL8483, ISL8488, ISL8489)
Single Unit Load Allows up to 32 Devices on the Bus
1nA Low Current Shutdown Mode (ISL8483)
Low Quiescent Current:
- 160
A (ISL8483, ISL8488, ISL8489)
- 340
A (ISL8485, ISL8490, ISL8491)
-7V to +12V Common Mode Input Voltage Range
Three State Rx and Tx Outputs (Except ISL8488,
ISL8490)
30ns Propagation Delays, 5ns Skew (ISL8485, ISL8490,
ISL8491)
Full Duplex and Half Duplex Pinouts
Operate from a Single +5V Supply (10% Tolerance)
Current Limiting and Thermal Shutdown for driver
Overload Protection
Applications
Factory Automation
Security Networks
Building Environmental Control Systems
Industrial/Process Control Networks
Level Translators (e.g., RS-232 to RS-422)
RS-232 "Extension Cords"
TABLE 1. SUMMARY OF FEATURES
PART
NUMBER
HALF/FULL
DUPLEX
NO. OF DEVICES
ALLOWED ON BUS
DATA RATE
(Mbps)
SLEW-RATE
LIMITED?
RECEIVER/
DRIVER ENABLE?
QUIESCENT
I
CC
(
A)
LOW POWER
SHUTDOWN?
PIN
COUNT
ISL8483
Half
32
0.25
Yes
Yes
160
Yes
8
ISL8485
Half
32
5
No
Yes
340
No
8
ISL8488
Full
32
0.25
Yes
No
160
No
8
ISL8489
Full
32
0.25
Yes
Yes
160
No
14
ISL8490
Full
32
5
No
No
340
No
8
ISL8491
Full
32
5
No
Yes
340
No
14
Data Sheet
December 2003
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143
|
Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2003. All Rights Reserved.
All other trademarks mentioned are the property of their respective owners.
2
Pinouts
ISL8483, ISL8485 (PDIP, SOIC)
TOP VIEW
ISL8488, ISL8490 (PDIP, SOIC)
TOP VIEW
ISL8489, ISL8491 (PDIP, SOIC)
TOP VIEW
Ordering Information
PART NO.
(BRAND)
TEMP.
RANGE (
o
C)
PACKAGE
PKG. DWG. #
ISL8483IB
(8483IB)
-40 to 85
8 Ld SOIC
M8.15
ISL8483IB-T
(8483IB)
-40 to 85
8 Ld SOIC
Tape and Reel
M8.15
ISL8483IP
-40 to 85
8 Ld PDIP
E8.3
ISL8485CB
(8485CB)
0 to 70
8 Ld SOIC
M8.15
ISL8485CB-T
(8485CB)
0 to 70
8 Ld SOIC
Tape and Reel
M8.15
ISL8485CP
0 to 70
8 Ld PDIP
E8.3
ISL8485IB
(8485IB)
-40 to 85
8 Ld SOIC
M8.15
ISL8485IB-T
(8485IB)
-40 to 85
8 Ld SOIC
Tape and Reel
M8.15
ISL8485IP
-40 to 85
8 Ld PDIP
E8.3
ISL8488IB
(8488IB)
-40 to 85
8 Ld SOIC
M8.15
ISL8488IB-T
(8488IB)
-40 to 85
8 Ld SOIC
Tape and Reel
M8.15
ISL8488IP
-40 to 85
8 Ld PDIP
E8.3
ISL8489IB
-40 to 85
14 Ld SOIC
M14.15
ISL8489IB-T
-40 to 85
14 Ld SOIC
Tape and Reel
M14.15
ISL8489IP
-40 to 85
14 Ld PDIP
E14.3
ISL8490IB
(8490IB)
-40 to 85
8 Ld SOIC
M8.15
ISL8490IB-T
(8490IB)
-40 to 85
8 Ld SOIC
Tape and Reel
M8.15
ISL8490IP
-40 to 85
8 Ld PDIP
E8.3
ISL8491IB
-40 to 85
14 Ld SOIC
M14.15
ISL8491IB-T
-40 to 85
14 Ld SOIC
Tape and Reel
M14.15
ISL8491IP
-40 to 85
14 Ld PDIP
E14.3
RO
RE
DE
DI
1
2
3
4
8
7
6
5
V
CC
B/Z
A/Y
GND
D
R
V
CC
RO
DI
GND
1
2
3
4
8
7
6
5
A
B
Z
Y
D
R
NC
RO
RE
DE
DI
GND
GND
V
CC
NC
A
B
Z
Y
NC
1
2
3
4
5
6
7
14
13
12
11
10
9
8
D
R
ISL8483, ISL8485, ISL8488, ISL8489, ISL8490, ISL8491
3
Truth Tables
TRANSMITTING
INPUTS
OUTPUTS
RE
DE
DI
Z
Y
X
1
1
0
1
X
1
0
1
0
0
0
X
High-Z
High-Z
1
0
X
High-Z *
High-Z *
*Shutdown Mode for ISL8483 (see Note 7)
RECEIVING
INPUTS
OUTPUT
RE
DE
Half Duplex
DE
Full Duplex
A-B
RO
0
0
X
+0.2V
1
0
0
X
-0.2V
0
0
0
X
Inputs Open
1
1
0
0
X
High-Z *
1
1
1
X
High-Z
*Shutdown Mode for ISL8483 (see Note 7)
Pin Descriptions
PIN
FUNCTION
RO
Receiver output: If A > B by at least 0.2V, RO is high; If A < B by 0.2V or more, RO is low; RO = High if A and B are unconnected (floating).
RE
Receiver output enable. RO is enabled when RE is low; RO is high impedance when RE is high.
DE
Driver output enable. The driver outputs, Y and Z, are enabled by bringing DE high. They are high impedance when DE is low.
DI
Driver input. A low on DI forces output Y low and output Z high. Similarly, a high on DI forces output Y high and output Z low.
GND
Ground connection.
A/Y
Noninverting receiver input and noninverting driver output. Pin is an input (A) if DE = 0; pin is an output (Y) if DE = 1.
B/Z
Inverting receiver input and inverting driver output. Pin is an input (B) if DE = 0; pin is an output (Z) if DE = 1.
A
Noninverting receiver input.
B
Inverting receiver input.
Y
Noninverting driver output.
Z
Inverting driver output.
V
CC
System power supply input (4.5V to 5.5V).
NC
No Connection.
ISL8483, ISL8485, ISL8488, ISL8489, ISL8490, ISL8491
4
Typical Operating Circuits
ISL8483, ISL8485
ISL8488, ISL8490
ISL8489, ISL8491
0.1
F
+
D
R
7
6
8
1
2
3
4
5
V
CC
GND
RO
RE
DE
DI
A/Y
B/Z
+5V
0.1
F
+
D
R
6
7
8
1
2
3
4
5
V
CC
GND
RO
RE
DE
DI
A/Y
B/Z
+5V
R
T
R
T
0.1
F
+
D
R
8
7
6
5
1
2
3
4
V
CC
GND
RO
DI
A
B
Y
Z
+5V
0.1
F
+
D
R
8
7
6
5
1
2
3
4
V
CC
GND
RO
DI
A
B
Y
Z
+5V
R
T
R
T
0.1
F
+
D
R
12
11
10
9
14
2
3
4
5
6, 7
V
CC
GND
RO
RE
DE
DI
A
B
Y
Z
+5V
0.1
F
+
D
R
12
11
10
9
14
2
3
4
5
6, 7
V
CC
GND
RO
RE
DE
DI
A
B
Y
Z
+5V
R
T
R
T
ISL8483, ISL8485, ISL8488, ISL8489, ISL8490, ISL8491
5
Absolute Maximum Ratings
Thermal Information
V
CC
to Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7V
Input Voltages
DI, DE, RE . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to (V
CC
+0.5V)
Input/Output Voltages
A, B, Y, Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -8V to +12.5V
RO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to (V
CC
+0.5V)
Short Circuit Duration
Y, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous
ESD Rating
HBM (Per MIL-STD-883, Method 3015.7) . . . . . . . . . . . . . . >7kV
Operating Conditions
Temperature Range
ISL84XXCX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0
o
C to 70
o
C
ISL84XXIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40
o
C to 85
o
C
Thermal Resistance (Typical, Note 1)
JA
(
o
C/W)
8 Ld SOIC Package . . . . . . . . . . . . . . . . . . . . . . . . .
170
8 Ld PDIP Package . . . . . . . . . . . . . . . . . . . . . . . . .
140
14 Ld SOIC Package . . . . . . . . . . . . . . . . . . . . . . . .
120
14 Ld PDIP Package . . . . . . . . . . . . . . . . . . . . . . . .
100
Moisture Sensitivity (see Technical Brief TB363)
All Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Level 1
Maximum Junction Temperature (Plastic Package) . . . . . . . 150
o
C
Maximum Storage Temperature Range . . . . . . . . . -65
o
C to 150
o
C
Maximum Lead Temperature (Soldering 10s) . . . . . . . . . . . . 300
o
C
(SOIC - Lead Tips Only)
CAUTION: Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
NOTE:
1.
JA
is measured with the component mounted on a low effective thermal conductivity test board in free air. See Tech Brief TB379 for details.
Electrical Specifications
Test Conditions: V
CC
= 4.5V to 5.5V; Unless Otherwise Specified.
Typicals are at V
CC
= 5V, T
A
= 25
o
C, Note 2
PARAMETER
SYMBOL
TEST CONDITIONS
TEMP
(
o
C)
MIN
TYP
MAX
UNITS
DC CHARACTERISTICS
Driver Differential V
OUT
(no load)
V
OD1
Full
-
-
V
CC
V
Driver Differential V
OUT
(with load)
V
OD2
R = 50
(RS-422), Figure 1
Full
2
3
-
V
R = 27
(RS-485), Figure 1
Full
1.5
2.3
5
V
Change in Magnitude of Driver
Differential V
OUT
for
Complementary Output States
V
OD
R = 27
or 50
, Figure 1
Full
-
0.01
0.2
V
Driver Common-Mode V
OUT
V
OC
R = 27
or 50
, Figure 1
Full
-
-
3
V
Change in Magnitude of Driver
Common-Mode V
OUT
for
Complementary Output States
V
OC
R = 27
or 50
, Figure 1
Full
-
0.01
0.2
V
Logic Input High Voltage
V
IH
DE, DI, RE
Full
2
-
-
V
Logic Input Low Voltage
V
IL
DE, DI, RE
Full
-
-
0.8
V
Logic Input Current
I
IN1
DE, DI, RE (ISL8483)
Full
-2
-
2
A
I
IN1
DI (ISL8485 -
ISL8491)
Full
-2
-
2
A
I
IN1
DE,
RE (ISL8485, ISL8489, ISL8491)
Full
-25
-
25
A
Input Current (A, B), Note 10
I
IN2
DE = 0V, V
CC
= 0V or
4.5 to 5.5V
V
IN
= 12V
Full
-
-
1
mA
V
IN
= -7V
Full
-
-
-0.8
mA
Receiver Differential Threshold
Voltage
V
TH
-7V
V
CM
12V
Full
-0.2
-
0.2
V
Receiver Input Hysteresis
V
TH
V
CM
= 0V
25
-
70
-
mV
Receiver Output High Voltage
V
OH
I
O
= -4mA, V
ID
= 200mV
Full
3.5
-
-
V
Receiver Output Low Voltage
V
OL
I
O
= -4mA, V
ID
= 200mV
Full
-
-
0.4
V
Three-State (high impedance)
Receiver Output Current
I
OZR
0.4V
V
O
2.4V
Full
-
-
1
A
ISL8483, ISL8485, ISL8488, ISL8489, ISL8490, ISL8491
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