1
FN6074.2
ISL4489E, ISL4491E
15kV ESD Protected, 1/8 Unit Load, 5V,
Low Power, High Speed and Slew Rate
Limited, Full Duplex, RS-485/RS-422
Transceivers
The ISL4489E, ISL4491E are ESD protected, "fractional"
unit load, BiCMOS, 5V powered, single transceivers that
meet both the RS-485 and RS-422 standards for balanced
communication. Each driver output and receiver input is
protected against 15kV ESD strikes, without latch-up.
Unlike competitive versions, these Intersil devices are
specified for 10% tolerance supplies (4.5V to 5.5V).
Rx inputs and Tx outputs present a "1/8 unit load" to the
RS-485 bus, which allows a total of 256 transmitters and
receivers on the network for large node count systems.
These devices are configured for full duplex (separate Rx
input and Tx output pins) applications, so they are ideal for
RS-422 networks requiring high ESD tolerance on the bus
pins.
The ISL4489E utilizes a slew rate limited driver which
reduces EMI, and minimizes reflections from improperly
terminated transmission lines, or unterminated stubs in
multidrop and multipoint applications.
Data rates up to 15Mbps are achievable by using the
ISL4491E, which features higher slew rates.
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.
Features
Pb-free Available as an Option (RoHS Compliant)
(See Ordering Info)
RS-485 I/O Pin ESD Protection
. . . . . . . . . . . . .
15kV HBM
- Class 3 ESD Level on all Other Pins . . . . . . >7kV HBM
1/8 Unit Load Allows up to 256 Devices on the Bus
High Data Rates (ISL4491E) . . . . . . . . . . . up to 15Mbps
Slew Rate Limited Version for Error Free Data
Transmission (ISL4489E)
Very Low Quiescent Current:
- 140
A (ISL4489E)
- 370
A (ISL4491E)
-7V to +12V Common Mode Input Voltage Range
Three-State Rx and Tx Outputs
Full Duplex Pinout
Operates 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
HIGH ESD?
NO. OF DEVICES
ALLOWED ON BUS
DATA RATE
(Mbps)
SLEW-RATE
LIMITED?
RECEIVER/
DRIVER ENABLE?
QUIESCENT
I
CC
(
A)
PIN
COUNT
ISL4489E
Full
Yes
256
0.25
Yes
Yes
140
14
ISL4491E
Full
Yes
256
15
No
Yes
370
14
Data Sheet
October 27, 2004
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. 2004. All Rights Reserved.
All other trademarks mentioned are the property of their respective owners.
2
FN6074.2
Pinout
ISL4489E, ISL4491E (SOIC)
TOP VIEW
Truth Tables
Ordering Information
PART NO.
TEMP.
RANGE (C)
PACKAGE
PKG.
DWG. #
ISL4489EIB
-40 to 85
14 Ld SOIC
M14.15
ISL4489EIB-T
-40 to 85
14 Ld SOIC
Tape and Reel
M14.15
ISL4489EIBZ (Note)
-40 to 85
14 Ld SOIC (Pb-free)
M14.15
ISL4489EIBZ-T
(Note)
-40 to 85
14 Ld SOIC
Tape and Reel (Pb-free)
M14.15
ISL4491EIB
-40 to 85
14 Ld SOIC
M14.15
ISL4491EIB-T
-40 to 85
14 Ld SOIC
Tape and Reel
M14.15
NOTE: Intersil Pb-free products employ special Pb-free material sets;
molding compounds/die attach materials and 100% matte tin plate
termination finish, which are RoHS compliant and compatible with
both SnPb and Pb-free soldering operations. Intersil Pb-free products
are MSL classified at Pb-free peak reflow temperatures that meet or
exceed the Pb-free requirements of IPC/JEDEC J STD-020C.
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
TRANSMITTING
INPUTS
OUTPUTS
RE
DE
DI
Z
Y
X
1
1
0
1
X
1
0
1
0
X
0
X
High-Z
High-Z
RECEIVING
INPUTS
OUTPUT
RE
DE
A-B
RO
0
X
+0.2V
1
0
X
-0.2V
0
0
X
Inputs Open
1
1
X
X
High-Z
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
15kV HBM ESD Protected, Noninverting receiver input.
B
15kV HBM ESD Protected, Inverting receiver input.
Y
15kV HBM ESD Protected, Noninverting driver output.
Z
15kV HBM ESD Protected, Inverting driver output.
V
CC
System power supply input (4.5V to 5.5V).
NC
No Connection.
ISL4489E, ISL4491E
3
FN6074.2
Typical Operating Circuit
ISL4489E, ISL4491E
0.1F
+
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
0.1F
+
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
ISL4489E, ISL4491E
4
FN6074.2
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 . . . . . . . . . . . . . . . . . . . . . . . . . See Specification Table
Thermal Resistance (Typical, Note 1)
JA
(C/W)
14 Ld SOIC Package . . . . . . . . . . . . . . . . . . . . . . . .
128
Maximum Junction Temperature (Plastic Package) . . . . . . . 150C
Maximum Storage Temperature Range . . . . . . . . . . . -65C to 150C
Maximum Lead Temperature (Soldering 10s) . . . . . . . . . . . . 300C
(Lead Tips Only)
Operating Conditions
Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . -40C to 85C
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
= 25C,
Note 2
PARAMETER
SYMBOL
TEST CONDITIONS
TEMP
(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
DI
Full
-2
-
2
A
DE, RE
Full
-40
-
40
A
Input Current (A, B) (Note 5)
I
IN2
DE = 0V, V
CC
= 0V or
4.5 to 5.5V
V
IN
= 12V
Full
-
-
130
A
V
IN
= -7V
Full
-100
-
-
A
Driver Three-State (high
impedance) Output Current (Y, Z)
I
OZD
-7V
V
O
12V
Full
-100
-
100
A
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
Receiver Input Resistance
R
IN
-7V
V
CM
12V
Full
92
120
-
k
No-Load Supply Current (Note 3)
I
CC
ISL4489E, DE, DI, RE = 0V or V
CC
Full
-
140
190
A
ISL4491E, DE, DI, RE = 0V or V
CC
Full
-
370
460
A
Driver Short-Circuit Current,
V
O
= High or Low
I
OSD1
DE = V
CC
, -7V
V
Y
or V
Z
12V (Note 4)
Full
35
-
250
mA
Receiver Short-Circuit Current
I
OSR
0V
V
O
V
CC
Full
7
-
85
mA
ISL4489E, ISL4491E
5
FN6074.2
SWITCHING CHARACTERISTICS (ISL4489E)
Driver Input to Output Delay
t
PLH
, t
PHL
R
DIFF
= 54
, C
L
= 100pF (Figure 2)
Full
250
400
2000
ns
Driver Output Skew
t
SKEW
R
DIFF
= 54
, C
L
= 100pF (Figure 2)
Full
-
160
800
ns
Driver Differential Rise or Fall Time
t
R
, t
F
R
DIFF
= 54
, C
L
= 100pF (Figure 2)
Full
250
600
2000
ns
Driver Enable to Output High
t
ZH
C
L
= 100pF, SW = GND (Figure 3)
Full
250
1000
2000
ns
Driver Enable to Output Low
t
ZL
C
L
= 100pF, SW = V
CC
(Figure 3)
Full
250
860
2000
ns
Driver Disable from Output High
t
HZ
C
L
= 15pF, SW = GND (Figure 3)
Full
300
660
3000
ns
Driver Disable from Output Low
t
LZ
C
L
= 15pF, SW = V
CC
(Figure 3)
Full
300
640
3000
ns
Receiver Input to Output Delay
t
PLH
, t
PHL
Figure 4
Full
250
500
2000
ns
Receiver Skew | t
PLH
- t
PHL
|
t
SKD
Figure 4
25
-
60
-
ns
Receiver Enable to Output High
t
ZH
C
L
= 15pF, SW = GND (Figure 5)
Full
-
10
50
ns
Receiver Enable to Output Low
t
ZL
C
L
= 15pF, SW = V
CC
(Figure 5)
Full
-
10
50
ns
Receiver Disable from Output High
t
HZ
C
L
= 15pF, SW = GND (Figure 5)
Full
-
10
50
ns
Receiver Disable from Output Low
t
LZ
C
L
= 15pF, SW = V
CC
(Figure 5)
Full
-
10
50
ns
Maximum Data Rate
f
MAX
Full
250
-
-
kbps
SWITCHING CHARACTERISTICS (ISL4491E)
Driver Input to Output Delay
t
PLH
, t
PHL
R
DIFF
= 54
, C
L
= 100pF (Figure 2)
Full
13
24
40
ns
Driver Output Skew
t
SKEW
R
DIFF
= 54
, C
L
= 100pF (Figure 2)
Full
-
3
10
ns
Driver Differential Rise or Fall Time
t
R
, t
F
R
DIFF
= 54
, C
L
= 100pF (Figure 2)
Full
5
12
20
ns
Driver Enable to Output High
t
ZH
C
L
= 100pF, SW = GND (Figure 3)
Full
-
14
70
ns
Driver Enable to Output Low
t
ZL
C
L
= 100pF, SW = V
CC
(Figure 3)
Full
-
14
70
ns
Driver Disable from Output High
t
HZ
C
L
= 15pF, SW = GND (Figure 3)
Full
-
44
70
ns
Driver Disable from Output Low
t
LZ
C
L
= 15pF, SW = V
CC
(Figure 3)
Full
-
21
70
ns
Receiver Input to Output Delay
t
PLH
, t
PHL
(Figure 4)
Full
30
90
150
ns
Receiver Skew | t
PLH
- t
PHL
|
t
SKD
(Figure 4)
25
-
5
-
ns
Receiver Enable to Output High
t
ZH
C
L
= 15pF, SW = GND (Figure 5)
Full
-
9
50
ns
Receiver Enable to Output Low
t
ZL
C
L
= 15pF, SW = V
CC
(Figure 5)
Full
-
9
50
ns
Receiver Disable from Output High
t
HZ
C
L
= 15pF, SW = GND (Figure 5)
Full
-
9
50
ns
Receiver Disable from Output Low
t
LZ
C
L
= 15pF, SW = V
CC
(Figure 5)
Full
-
9
50
ns
Maximum Data Rate
f
MAX
Full
15
-
-
Mbps
ESD PERFORMANCE
RS-485 Pins (A, B, Y, Z)
Human Body Model
25
-
15
-
kV
All Other Pins
25
-
>
7
-
kV
NOTES:
2. All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to device ground unless
otherwise specified.
3. Supply current specification is valid for loaded drivers when DE = 0V.
4. Applies to peak current. See "Typical Performance Curves" for more information.
5. Devices meeting these limits are denoted as "1/8 unit load (1/8 UL)" transceivers. The RS-485 standard allows up to 32 Unit Loads on the bus,
so there can be 256 1/8 UL devices on a bus.
Electrical Specifications
Test Conditions: V
CC
= 4.5V to 5.5V; Unless Otherwise Specified. Typicals are at V
CC
= 5V, T
A
= 25C,
Note 2 (Continued)
PARAMETER
SYMBOL
TEST CONDITIONS
TEMP
(C)
MIN
TYP
MAX
UNITS
ISL4489E, ISL4491E
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