DATASHEET

Data Sheet
T
DUC
CT
PRO PRODU
E
T
E
E
L
T
O
U
OBS UBSTIT E
E S L3158
SIBL
IS
POS
ISL3158AE
October 15, 2013
±16.5kV ESD (IEC61000-4-2) Protected,
Large Output Swing, 5V, Full Fail-Safe, 1/8
Unit Load, RS-485/RS-422 Transceiver
The ISL3158AE is a BiCMOS, IEC61000 ESD protected, 5V
powered, single transceiver that meets both the RS-485 and
RS-422 standards for balanced communication. Each driver
output and receiver input is protected against ±16.5kV ESD
strikes without latch-up.
The ISL3158AE transmitter delivers exceptional differential
output voltages (2.4V min), into the RS-485 required 54
load, for better noise immunity or to allow up to eight 120
terminations in “star” or other non-standard bus topologies.
This device has very low bus currents (+125µA/-75µA), so it
presents a true “1/8 unit load” to the RS-485 bus. This allows
up to 256 transceivers on the network without violating the
RS-485 specification’s 32 unit load maximum, and without
using repeaters.
Receiver (Rx) inputs feature a “Full Fail-Safe” design, which
ensures a logic high Rx output if Rx inputs are floating,
shorted, or on a terminated but undriven bus. Rx outputs
feature high drive levels - typically 28mA @ VOL = 1V (to
ease the design of optocoupled isolated interfaces).
Hot Plug circuitry ensures that the Tx and Rx outputs remain
in a high impedance state until the power supply has
stabilized, and the Tx outputs are fully short circuit protected.
FN6886.1
Features
• High Driver VOD . . . . . . . . . . . . . . 2.4V (Min) @ RD = 54
- Better Noise Immunity, or Drive Up to 8 Terminations
• IEC61000 ESD Protection on RS-485 I/O Pins . . ±16.5kV
- Class 3 ESD Level on all Other Pins . . . . . . >7kV HBM
• Full Fail-safe (Open, Short, Terminated and Undriven)
Receivers
• High Rx IOL to Drive Opto-Couplers for Isolated
Applications
• Hot Plug Circuitry - Tx and Rx Outputs Remain
Three-State During Power-up/Power-down
• True 1/8 Unit Load Allows up to 256 Devices on the Bus
• Specified for Single 5V, 10% Tolerance, Supplies
• High Data Rates . . . . . . . . . . . . . . . . . . . . . up to 10Mbps
• Low Quiescent Supply Current . . . . . . . . . . . . . . . . 600µA
Ultra Low Shutdown Supply Current . . . . . . . . . . . . .70nA
• -7V to +12V Common Mode Input Voltage Range
• Half Duplex Pinouts
• Pb-free (RoHS compliant)
• Three-State Rx and Tx Outputs
• Current Limiting for Driver Overload Protection
Applications
The ISL3158AE is a half duplex version. It multiplexes the
Rx inputs and Tx outputs to allow transceivers with output
disable functions in an 8 Ld package.
• Utility Meters and Automated Meter Reading Systems
• High Node Count Systems
• PROFIBUS® and Field Bus Networks, and Factory
Automation
• Security Camera Networks
• Building Lighting and Environmental Control Systems
• Industrial/Process Control Networks
TABLE 1. SUMMARY OF FEATURES
PART
NUMBER
HALF/FUL
L DUPLEX
DATA RATE
(Mbps)
ISL3158AEM
Half
10
No
Yes
ISL3158AEMW
Half
10
No
Yes
1
SLEW-RATE
# DEVICES
LIMITED?
HOT PLUG ON BUS
Rx/Tx
ENABLE?
QUIESCENT
ICC (µA)
256
Yes
600
Yes
8
256
Yes
600
Yes
N/A
LOW POWER
PIN
SHUTDOWN? COUNT
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2009, 2013. All Rights Reserved
Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
ISL3158AE
Pinout
ISL3158AE
(8 LD SOIC)
TOP VIEW
RO 1
8
VCC
RE 2
7
B/Z
DE 3
6
A/Y
5
GND
DI 4
R
D
Ordering Information
PART NUMBER
(Notes 2, 3)
ISL3158AEMBZ (Note 1)
PART
MARKING
3158A EMBZ
ISL3158AEMW
TEMP. RANGE
(°C)
-55 to +125
-55 to +125
PACKAGE
(Pb-Free)
8 Ld SOIC
PKG.
DWG. #
M8.15
Wafer
NOTES:
1. Add “-T*” suffix for tape and reel. Please refer to TB347 for details on reel specifications.
2. These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte
tin plate plus anneal (e3 termination finish, which is 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-020.
3. For Moisture Sensitivity Level (MSL), please see device information page for ISL3158AE. For more information on MSL, please see tech brief
TB363.
2
FN6886.1
October 15, 2013
ISL3158AE
Truth Tables
RECEIVING
TRANSMITTING
INPUTS
INPUTS
OUTPUTS
RE
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*
NOTE: *Shutdown Mode (See Note 10).
OUTPUT
DE
DE
Half Duplex Full Duplex
A-B
RO
0
0
X
 -0.05V
1
0
0
X
 -0.2V
0
0
0
X
Inputs
Open/Shorted
1
1
0
0
X
High-Z*
1
1
1
X
High-Z
NOTE: *Shutdown Mode (See Note 10).
Pin Descriptions
PIN
FUNCTION
RO
Receiver output: If A-B  -50mV, RO is high; If A-B  -200mV, RO is low; RO = High if A and B are unconnected (floating) or shorted.
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
±16.5kV IEC61000 ESD Protected RS-485/RS-422 level, non-inverting receiver input and noninverting driver output. Pin is an input
if DE = 0; pin is an output if DE = 1.
B/Z
±16.5kV IEC61000 ESD Protected RS-485/RS-422 level, inverting receiver input and inverting driver output. Pin is an input if DE = 0;
pin is an output if DE = 1.
VCC
System power supply input (4.5V to 5.5V).
3
FN6886.1
October 15, 2013
ISL3158AE
Typical Operating Circuit
ISL3158AE
+5V
+5V
+
8
0.1µF
0.1µF
+
8
VCC
1 RO
VCC
R
D
2 RE
B/Z
7
3 DE
A/Y
6
4 DI
RT
RT
7
B/Z
DE 3
6
A/Y
RE 2
R
D
GND
GND
5
5
4
DI 4
RO 1
FN6886.1
October 15, 2013
ISL3158AE
Absolute Maximum Ratings
Thermal Information
VCC to Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7V
Input Voltages
DI, DE, RE . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to (VCC + 0.3V)
Input/Output Voltages
A/Y, B/Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -9V to +13V
A/Y, B/Z (Transient Pulse Through 100) . . . . . . . . . . . . . . ±25V
RO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to (VCC +0.3V)
Short Circuit Duration
Y, Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous
ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . See Specifications Table
Thermal Resistance (Typical, Note 4)
JA (°C/W)
8 Ld SOIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
120
Maximum Junction Temperature (Plastic Package) . . . . . . +150°C
Maximum Storage Temperature Range . . . . . . . . . .-65°C to +150°C
Pb-Free Reflow Profile. . . . . . . . . . . . . . . . . . . . . . . . .see link below
http://www.intersil.com/pbfree/Pb-FreeReflow.asp
Operating Conditions
Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . .-55°C to +125°C
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and
result in failures not covered by warranty.
NOTE:
4. JA is measured with the component mounted on a high effective thermal conductivity test board in free air. See Tech Brief TB379 for details.
Electrical Specifications
Test Conditions: VCC = 4.5V to 5.5V; Unless Otherwise Specified. Typicals are at VCC = 5V, TA = +25°C
(Note 5). Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified.
Temperature limits established by characterization and are not production tested.
PARAMETER
TEMP
(°C)
MIN
TYP
MAX
UNITS
Full
-
-
VCC
V
RL = 100 (RS-422) (Figure 1A)
Full
2.8
3.6
-
V
RL = 54 (RS-485) (Figure 1A)
Full
2.4
3.1
VCC
V
RL = 15 (Eight 120 terminations) (Note 13)
25
-
1.65
-
V
RL = 60, -7V  VCM  12V (Figure 1B)
Full
2.4
3
-
V
VOD
RL = 54 or 100 (Figure 1A)
Full
-
0.01
0.2
V
VOC
RL = 54 or 100 (Figure 1A)
Full
-
-
3.15
V
VOC
RL = 54 or 100 (Figure 1A)
Full
-
0.01
0.2
V
SYMBOL
TEST CONDITIONS
DC CHARACTERISTICS
Driver Differential VOUT (No load)
VOD1
Driver Differential VOUT (Loaded)
VOD2
Change in Magnitude of Driver
Differential VOUT for
Complementary Output States
Driver Common-Mode VOUT
Change in Magnitude of Driver
Common-Mode VOUT for
Complementary Output States
Logic Input High Voltage
VIH
DE, DI, RE
Full
2
-
-
V
Logic Input Low Voltage
VIL
DE, DI, RE
Full
-
-
0.8
V
25
-
100
-
mV
DI Input Hysteresis Voltage
VHYS
Logic Input Current
IIN1
DE, DI, RE
Full
-2
-
2
µA
Input Current (A/Y, B/Z)
IIN2
DE = 0V, VCC = 0V or 5.5V VIN = 12V
Full
-
70
125
µA
VIN = -7V
Full
-75
55
-
µA
DE = VCC, -7V  VY or VZ  12V (Note 7)
Full
-
-
±250
mA
-7V  VCM  12V (Note 15)
Full
-200
-90
-50
mV
Driver Short-Circuit Current,
VO = High or Low
IOSD1
Receiver Differential Threshold
Voltage
VTH
Receiver Input Hysteresis
VTH
VCM = 0V
25
-
20
-
mV
Receiver Output High Voltage
VOH
IO = -8mA, VID = -50mV
Full
VCC - 1.2
4.3
-
V
Receiver Output Low Voltage
VOL
IO = -8mA, VID = -200mV
Full
-
0.25
0.5
V
Receiver Output Low Current
IOL
VO = 1V, VID = -200mV
Full
15
28
-
mA
5
FN6886.1
October 15, 2013
ISL3158AE
Electrical Specifications
Test Conditions: VCC = 4.5V to 5.5V; Unless Otherwise Specified. Typicals are at VCC = 5V, TA = +25°C
(Note 5). Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified.
Temperature limits established by characterization and are not production tested. (Continued)
PARAMETER
SYMBOL
TEST CONDITIONS
TEMP
(°C)
MIN
TYP
MAX
UNITS
Three-State (High Impedance)
Receiver Output Current
IOZR
0.4V  VO  2.4V
Full
-1
0.03
1
µA
Receiver Input Resistance
RIN
-7V  VCM  12V
Full
96
160
-
k
0V  VO  VCC
Full
±7
65
±85
mA
Half Duplex Versions, DE = VCC, RE = X,
DI = 0V or VCC
Full
-
650
800
µA
All Versions, DE = 0V, RE = 0V, or Full Duplex
Versions, DE = VCC, RE = X. DI = 0V or VCC
Full
-
550
700
µA
DE = 0V, RE = VCC, DI = 0V or VCC
Full
-
0.07
3
µA
IEC61000-4-2, Air-Gap
Discharge Method
25
-
±16.5
-
kV
IEC61000-4-2, Contact Discharge Method
25
-
±9
-
kV
Human Body Model, From Bus Pins to GND
25
-
±16.5
-
kV
Human Body Model, per MIL-STD-883 Method
3015
25
-
±7
-
kV
Machine Model
25
-
400
-
V
Receiver Short-Circuit Current
IOSR
SUPPLY CURRENT
No-Load Supply Current (Note 6)
Shutdown Supply Current
ICC
ISHDN
ESD PERFORMANCE
RS-485 Pins (A/Y, B/Z)
All Pins
1/2 Duplex
DRIVER SWITCHING CHARACTERISTICS (ISL3158AE)
Driver Differential Output Delay
tPLH, tPHL
RDIFF = 54, CL = 100pF (Figure 2)
Full
-
21
30
ns
Driver Differential Output Skew
tSKEW
RDIFF = 54, CL = 100pF (Figure 2)
Full
-
0.2
3
ns
Driver Differential Rise or Fall Time
tR, tF
RDIFF = 54, CL = 100pF (Figure 2)
Full
-
12
16
ns
Maximum Data Rate
fMAX
CD = 470pF (Figure 4), (Note 15)
Full
-
10
-
Mbps
Driver Enable to Output High
tZH
RL = 500, CL = 100pF, SW = GND (Figure 3),
(Note 8)
Full
-
30
45
ns
Driver Enable to Output Low
tZL
RL = 500, CL = 100pF, SW = VCC (Figure 3),
(Note 8)
Full
-
28
45
ns
Driver Disable from Output Low
tLZ
RL = 500, CL = 15pF, SW = VCC (Figure 3)
Full
-
50
65
ns
Driver Disable from Output High
tHZ
RL = 500, CL = 15pF, SW = GND (Figure 3)
Full
-
38
65
ns
(Notes 10, 15)
Full
-
160
-
ns
Time to Shutdown
tSHDN
Driver Enable from Shutdown to
Output High
tZH(SHDN) RL = 500, CL = 100pF, SW = GND (Figure 3),
(Notes 10, 11)
Full
-
-
200
ns
Driver Enable from Shutdown to
Output Low
tZL(SHDN)
RL = 500, CL = 100pF, SW = VCC (Figure 3),
(Notes 10, 11)
Full
-
-
200
ns
Full
-
10
-
Mbps
Full
-
33
50
ns
(Figure 5)
Full
-
2.5
5
ns
RL = 1k, CL = 15pF, SW = VCC (Figure 6),
(Note 9)
Full
-
8
15
ns
RECEIVER SWITCHING CHARACTERISTICS (ISL3158AE)
Maximum Data Rate
fMAX
(Figure 5) (Note 15)
tPLH, tPHL (Figure 5)
Receiver Input to Output Delay
Receiver Skew | tPLH - tPHL |
tSKD
Receiver Enable to Output Low
tZL
6
FN6886.1
October 15, 2013
ISL3158AE
Electrical Specifications
Test Conditions: VCC = 4.5V to 5.5V; Unless Otherwise Specified. Typicals are at VCC = 5V, TA = +25°C
(Note 5). Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified.
Temperature limits established by characterization and are not production tested. (Continued)
PARAMETER
SYMBOL
TEST CONDITIONS
TEMP
(°C)
MIN
TYP
MAX
UNITS
Receiver Enable to Output High
tZH
RL = 1k, CL = 15pF, SW = GND (Figure 6),
(Note 9)
Full
-
7
15
ns
Receiver Disable from Output Low
tLZ
RL = 1k, CL = 15pF, SW = VCC (Figure 6)
Full
-
8
15
ns
Receiver Disable from Output High
tHZ
RL = 1k, CL = 15pF, SW = GND (Figure 6)
Full
-
8
15
ns
(Notes 10, 15)
Full
60
160
600
ns
Time to Shutdown
tSHDN
Receiver Enable from Shutdown to
Output High
tZH(SHDN) RL = 1k, CL = 15pF, SW = GND (Figure 6),
(Notes 10, 12)
Full
-
-
200
ns
Receiver Enable from Shutdown to
Output Low
tZL(SHDN)
RL = 1k, CL = 15pF, SW = VCC (Figure 6),
(Notes 10, 12)
Full
-
-
200
ns
NOTES:
5. 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.
6. Supply current specification is valid for loaded drivers when DE = 0V.
7. Applies to peak current. See “Typical Performance Curves” beginning on page 12 for more information.
8. Keep RE = 0 to prevent the device from entering SHDN.
9. The RE signal high time must be short enough (typically <100ns) to prevent the device from entering SHDN.
10. Transceivers are put into shutdown by bringing RE high and DE low. If the inputs are in this state for less than 60ns, the parts are guaranteed
not to enter shutdown. If the inputs are in this state for at least 600ns, the parts are guaranteed to have entered shutdown. See “Low Power
Shutdown Mode” on page 11.
11. Keep RE = VCC, and set the DE signal low time >600ns to ensure that the device enters SHDN.
12. Set the RE signal high time >600ns to ensure that the device enters SHDN.
13. See Figure 8 for more information, and for performance over-temperature.
14. For wafer sale, the switching test limits are established by characterization.
15. Limits established by characterization and are not production tested.
Test Circuits and Waveforms
VCC
RL/2
DE
DI
VCC
Z
DI
VOD
D
375
DE
Z
VOD
D
Y
Y
RL/2
FIGURE 1A. VOD AND VOC
RL = 60
VCM
-7V TO +12V
375
VOC
FIGURE 1B. VOD WITH COMMON MODE LOAD
FIGURE 1. DC DRIVER TEST CIRCUITS
7
FN6886.1
October 15, 2013
ISL3158AE
Test Circuits and Waveforms (Continued)
3V
DI
1.5V
1.5V
0V
tPHL
tPLH
VCC
OUT (Z)
VOH
OUT (Y)
VOL
CL = 100pF
DE
Z
DI
RDIFF
D
Y
CL = 100pF
90%
DIFF OUT (Y - Z)
10%
SIGNAL
GENERATOR
+VOD
90%
10%
tR
-VOD
tF
SKEW = |tPLH - tPHL|
FIGURE 2A. TEST CIRCUIT
FIGURE 2B. MEASUREMENT POINTS
FIGURE 2. DRIVER PROPAGATION DELAY AND DIFFERENTIAL TRANSITION TIMES
DE
Z
DI
500
VCC
D
SIGNAL
GENERATOR
SW
Y
GND
CL
3V
DE
PARAMETER OUTPUT
RE
DI
SW
CL (pF)
tHZ
Y/Z
X
1/0
GND
15
tLZ
Y/Z
X
0/1
VCC
15
tZH
Y/Z
0 (Note 8)
1/0
GND
100
tZL
Y/Z
0 (Note 8)
0/1
VCC
100
tZH(SHDN)
Y/Z
1 (Note 11)
1/0
GND
100
tZL(SHDN)
Y/Z
1 (Note 11)
0/1
VCC
100
NOTE 7
1.5V
1.5V
0V
tZH, tZH(SHDN)
OUTPUT HIGH
NOTE 7
tHZ
VOH - 0.5V
2.3V
OUT (Y, Z)
VOH
0V
tZL, tZL(SHDN)
tLZ
NOTE 7
VCC
OUT (Y, Z)
2.3V
OUTPUT LOW
FIGURE 3A. TEST CIRCUIT
VOL + 0.5V V
OL
FIGURE 3B. MEASUREMENT POINTS
FIGURE 3. DRIVER ENABLE AND DISABLE TIMES
VCC
DE
+
Z
DI
60
D
CD
Y
VOD
3V
DI
0V
-
SIGNAL
GENERATOR
+VOD
DIFF OUT (Y - Z)
-VOD
FIGURE 4A. TEST CIRCUIT
0V
FIGURE 4B. MEASUREMENT POINTS
FIGURE 4. DRIVER DATA RATE
8
FN6886.1
October 15, 2013
ISL3158AE
Test Circuits and Waveforms (Continued)
+1.5V
RE
0V
15pF
B
R
A
A
0V
RO
0V
-1.5V
tPHL
tPLH
VCC
SIGNAL
GENERATOR
1.5V
RO
1.5V
0V
FIGURE 5A. TEST CIRCUIT
FIGURE 5B. MEASUREMENT POINTS
FIGURE 5. RECEIVER PROPAGATION DELAY AND DATA RATE
RE
GND
B
A
1k
RO
R
SIGNAL
GENERATOR
15pF
VCC
SW
NOTE 7
GND
RE
3V
1.5V
1.5V
0V
PARAMETER
DE
A
+1.5V
SW
tHZ
0
tLZ
0
-1.5V
VCC
tZH (Note 9)
0
+1.5V
GND
tZL (Note 9)
0
-1.5V
VCC
tZH(SHDN) (Note 12)
0
+1.5V
GND
tZL(SHDN) (Note 12)
0
-1.5V
VCC
FIGURE 6A. TEST CIRCUIT
GND
tZH, tZH(SHDN)
NOTE 7
OUTPUT HIGH
tHZ
VOH - 0.5V
1.5V
RO
VOH
0V
tZL, tZL(SHDN)
tLZ
NOTE 7
VCC
RO
1.5V
OUTPUT LOW
VOL + 0.5V V
OL
FIGURE 6B. MEASUREMENT POINTS
FIGURE 6. RECEIVER ENABLE AND DISABLE TIMES
9
FN6886.1
October 15, 2013
ISL3158AE
Receiver (Rx) Features
This device utilizes a differential input receiver for maximum
noise immunity and common mode rejection. Input sensitivity
is better than 200mV, as required by the RS-422 and RS-485
specifications.
Rx outputs feature high drive levels (typically 28mA @
VOL = 1V to ease the design of optically coupled isolated
interfaces).
Receiver input resistance of 96k surpasses the RS-422
specification of 4k, and is eight times the RS-485 “Unit
Load (UL)” requirement of 12k minimum. Thus, this
product is known as a “one-eighth UL” transceiver, and there
can be up to 256 of these devices on a network while still
complying with the RS-485 loading specification.
Rx inputs function with common mode voltages as great as
±7V outside the power supplies (i.e., +12V and -7V), making
them ideal for long networks where induced voltages are a
realistic concern.
All the receivers include a “full fail-safe” function that
guarantees a high level receiver output if the receiver inputs
are unconnected (floating), shorted together, or connected to
a terminated bus with all the transmitters disabled.
Receivers easily meet the data rates supported by the
corresponding driver, and all receiver outputs are
three-statable via the active low RE input.
The ISL3158AE driver design delivers larger differential
output voltages (VOD) than the RS-485 standard requires, or
than most RS-485 transmitters can deliver. The minimum
±2.4V VOD guarantees at least ±900mV more noise
immunity than networks built using standard 1.5V VOD
transmitters.
Another advantage of the large VOD is the ability to drive
more than two bus terminations, which allows for utilizing the
ISL3158AE in “star” and other multi-terminated,
“non-standard” network topologies. Figure 8, details the
transmitter’s VOD vs IOUT characteristic, and includes load
lines for six (20) and eight (15) 120 terminations. The
figure shows that the driver typically delivers 1.65/1.5V into
6/8 terminations, even at the worst case temperature of
+85°C.The RS-485 standard requires a minimum 1.5V VOD
into two terminations, but the ISL3158AE delivers RS-485
voltage levels with 3x to 4x the number of terminations.
Hot Plug Function
When a piece of equipment powers up, there is a period of
time where the processor or ASIC driving the RS-485 control
lines (DE, RE) is unable to ensure that the RS-485 Tx and
Rx outputs are kept disabled. If the equipment is connected
to the bus, a driver activating prematurely during power-up
may crash the bus. To avoid this scenario, the ISL3158AE
devices incorporate a “Hot Plug” function. Circuitry monitoring
VCC ensures that, during power-up and power-down, the Tx
and Rx outputs remain disabled, regardless of the state of DE
and RE, if VCC is less than ~3.4V. This gives the
processor/ASIC a chance to stabilize and drive the RS-485
control lines to the proper states.
DE, DI = VCC
RE = GND
5.0
3.5V
VCC (V)
Another important advantage of RS-485 is the extended
common mode range (CMR), which specifies that the driver
outputs and receiver inputs withstand signals that range from
+12V to -7V. RS-422 and RS-485 are intended for long runs,
so the wide CMR is necessary to handle ground potential
differences, as well as voltages induced in the cable by
external fields.
High VOD Improves Noise Immunity and Flexibility
3.3V
2.5
VCC
0
5.0
RL = 1k
2.5
0
A/Y
ISL3158AE
RL = 1k
RO
ISL3158AE
5.0
2.5
0
Driver (Tx) Features
The RS-485/RS-422 driver is a differential output device that
delivers at least 2.4V across a 54 load (RS-485), and at
least 2.8V across a 100 load (RS-422). The driver features
low propagation delay skew to maximize bit width, and to
minimize EMI, and all drivers are three-stateable via the
active high DE input.
10
RECEIVER OUTPUT (V)
RS-485 and RS-422 are differential (balanced) data
transmission standards used for long haul or noisy
environments. RS-422 is a subset of RS-485, so RS-485
transceivers are also RS-422 compliant. RS-422 is a
point-to-multipoint (multidrop) standard, which allows only
one driver and up to 10 (assuming one unit load devices)
receivers on each bus. RS-485 is a true multipoint standard,
which allows up to 32 one unit load devices (any
combination of drivers and receivers) on each bus. To allow
for multipoint operation, the RS-485 specification requires
that drivers must handle bus contention without sustaining
any damage.
Outputs of the ISL3158AE driver is not limited, so faster
output transition times allow data rates of at least 10Mbps
DRIVER Y OUTPUT (V)
Application Information
TIME (40µs/DIV)
FIGURE 7. HOT PLUG PERFORMANCE (ISL3158AE) vs
ISL83088E WITHOUT HOT PLUG CIRCUITRY
FN6886.1
October 15, 2013
ISL3158AE
ESD Protection
All pins on this device includes class 3 (>7kV) Human Body
Model (HBM) ESD protection structures, but the RS-485
pins (driver outputs and receiver inputs) incorporate
advanced structures allowing them to survive ESD events
in excess of ±16.5kV HBM and ±16.5kV (1/2 duplex)
IEC61000-4-2. The RS-485 pins are particularly vulnerable
to ESD strikes because they typically connect to an
exposed port on the exterior of the finished product. Simply
touching the port pins, or connecting a cable, can cause an
ESD event that might destroy unprotected ICs. These new
ESD structures protect the device whether or not it is
powered up, and without degrading the RS-485 common
mode range of -7V to +12V. This built-in ESD protection
eliminates the need for board level protection structures
(e.g., transient suppression diodes), and the associated,
undesirable capacitive load they present.
IEC61000-4-2 Testing
The IEC61000 test method applies to finished equipment,
rather than to an individual IC. Therefore, the pins most likely
to suffer an ESD event are those that are exposed to the
outside world (the RS-485 pins in this case), and the IC is
tested in its typical application configuration (power applied)
rather than testing each pin-to-pin combination. The
IEC61000 standard’s lower current limiting resistor coupled
with the larger charge storage capacitor yields a test that is
much more severe than the HBM test. The extra ESD
protection built into this device’s RS-485 pins allows the
design of equipment meeting level 4 criteria without the need
for additional board level protection on the RS-485 port.
AIR-GAP DISCHARGE TEST METHOD
For this test method, a charged probe tip moves toward the
IC pin until the voltage arcs to it. The current waveform
delivered to the IC pin depends on approach speed,
humidity, temperature, etc., so it is difficult to obtain
repeatable results. The ISL3158AE 1/2 duplex RS-485 pins
withstand ±16.5kV air-gap discharges.
CONTACT DISCHARGE TEST METHOD
During the contact discharge test, the probe contacts the
tested pin before the probe tip is energized, thereby
eliminating the variables associated with the air-gap
discharge. The result is a more repeatable and predictable
test, but equipment limits prevent testing devices at voltages
higher than ±9kV. The RS-485 pins of all the ISL3158AE
versions survive ±9kV contact discharges.
Twisted pair is the cable of choice for RS-485/RS-422
networks. Twisted pair cables tend to pick up noise and
other electromagnetically induced voltages as common
mode signals, which are effectively rejected by the
differential receivers in these ICs.
Proper termination is imperative, when using the 10Mbps
devices, to minimize reflections. Terminations are
recommended unless power dissipation is an overriding
concern.
In point-to-point, or point-to-multipoint (single driver on bus)
networks, the main cable should be terminated in its
characteristic impedance (typically 120) at the end farthest
from the driver. In multi-receiver applications, stubs
connecting receivers to the main cable should be kept as
short as possible. Multipoint (multi-driver) systems require
that the main cable be terminated in its characteristic
impedance at both ends. Stubs connecting a transceiver to
the main cable should be kept as short as possible.
Built-In Driver Overload Protection
As stated previously, the RS-485 specification requires that
drivers survive worst case bus contentions undamaged.
These devices meet this requirement via driver output short
circuit current limit circuitry.
The driver output stages incorporate short circuit current
limiting circuitry which ensures that the output current never
exceeds the RS-485 specification, even at the common
mode voltage range extremes.
Low Power Shutdown Mode
This CMOS transceiver uses a fraction of the power required
by it’s bipolar counterparts, but it also includes a shutdown
feature that reduces the already low quiescent ICC to a 70nA
trickle. This device enters shutdown whenever the receiver
and driver are simultaneously disabled (RE = VCC and
DE = GND) for a period of at least 600ns. Disabling both the
driver and the receiver for less than 60ns guarantees that
the transceiver will not enter shutdown.
Note that receiver and driver enable times increase when
the transceiver enables from shutdown. Refer to Notes 8, 9,
10, 11 and 12, at the end of the “Electrical Specification”
table on page 6, for more information.
Data Rate, Cables, and Terminations
RS-485/RS-422 are intended for network lengths up to
4000’, but the maximum system data rate decreases as the
transmission length increases. Devices operating at 10Mbps
are limited to lengths of less than 100’.
11
FN6886.1
October 15, 2013
ISL3158AE
Typical Performance Curves
VCC = 5V, TA = +25°C; Unless Otherwise Specified.
140
3.8
+25°C
DIFFERENTIAL OUTPUT VOLTAGE
(V)
DRIVER OUTPUT CURRENT (mA)
130
120
+85°C
110
100
90
80
70
60
RD = 54
RD = 15
RD = 20
50
40
RD = 100
30
20
10
0
0
1
2
3
4
DIFFERENTIAL OUTPUT VOLTAGE (V)
3.6
3.5
3.4
3.3
3.2
FIGURE 8. DRIVER OUTPUT CURRENT vs DIFFERENTIAL
OUTPUT VOLTAGE
RDIFF = 54
3.1
3.0
2.9
2.8
-60
5
RDIFF = 100
3.7
-40
-20
0
20
40
60
TEMPERATURE (°C)
80
100
120
FIGURE 9. DRIVER DIFFERENTIAL OUTPUT VOLTAGE vs
TEMPERATURE
700
200
150
650
100
600
50
550
ICC (µA)
OUTPUT CURRENT (mA)
Y OR Z = LOW
0
-50
ICC DE-VCC
500
450
ICC DE-GND
400
-100
Y OR Z = HIGH
-150
-200
-7
350
-6
-4
-2
0
2
4
6
8
10
300
-60
12
-40
-20
0
OUTPUT VOLTAGE (V)
20
40
60
80
100
120
TEMPERATURE (°C)
FIGURE 10. DRIVER OUTPUT CURRENT vs SHORT CIRCUIT
VOLTAGE
FIGURE 11. SUPPLY CURRENT vs TEMPERATURE
0.9
0.8
29
0.7
27
0.6
SKEW (ns)
PROPOGATION DELAY (ns)
31
25
TPHL
23
0.5
0.4
0.3
21
0.2
TPLH
19
17
-60 -45 -30 -15
0.1
0
15
30
45
60
75
90
105 120
TEMPERATURE (°C)
FIGURE 12. DRIVER DIFFERENTIAL PROPAGATION DELAY
vs TEMPERATURE (ISL3158AE)
12
SKEW
0
-60 -45 -30 -15
0
15 30 45 60
TEMPERATURE (°C)
75
90
105 120
FIGURE 13. DRIVER DIFFERENTIAL SKEW vs
TEMPERATURE (ISL3158AE)
FN6886.1
October 15, 2013
ISL3158AE
RDIFF = 54, CL = 100pF
DI
5
0
5
RO
0
5
4
B/Z
3
2
A/Y
DRIVER INPUT (V)
VCC = 5V, TA = +25°C; Unless Otherwise Specified. (Continued)
60
RECEIVER OUTPUT CURRENT (mA)
DRIVER OUTPUT (V)
RECEIVER OUTPUT (V)
Typical Performance Curves
VOL, +25°C
50
VOL, +85°C
40
30
VOH, +25°C
20
10
0
1
TIME (20ns/DIV)
FIGURE 14. DRIVER AND RECEIVER WAVEFORMS,
(ISL3158AE)
13
VOH, +85°C
0
1
2
3
4
5
RECEIVER OUTPUT VOLTAGE (V)
FIGURE 15. RECEIVER OUTPUT CURRENT vs RECEIVER
OUTPUT VOLTAGE
FN6886.1
October 15, 2013
ISL3158AE
Die Characteristics
TABLE 2. BOND PAD FUNCTION AND COORDINATES
DIE DIMENSIONS INCLUDING 50ΜM SCRIBE
Thickness: 14 mils
1400µm x 1530µm
Interface Materials
GLASSIVATION
Sandwich TEOS and Nitride
TOP METALLIZATION
Type: Al with 0.5% Cu
Thickness: 28kÅ
SUBSTRATE
N/A
BACKSIDE FINISH
Silicon/Polysilicon/Oxide
Assembly Related Information
PAD #
FUNCTION
X
(µm)
Y
(µm)
1
RO
99.5
1308
2
RE
99.5
1014.35
3
DE
99.5
498.3
4
DI
99.5
286.75
5
GND2
574.3
104.7
6
GND1
684.3
104.7
7
Y
1054
250.6
8
A (half duplex)
1054
540.45
9
Z
1054
831.1
10
B
1054
1004.65
11
A (full duplex)
1054
1256.45
12
VCC
562.55
1385.35
SUBSTRATE POTENTIAL
GND (powered up)
Additional Information
WORST CASE CURRENT DENSITY
N/A
PROCESS
Si GateBiCMOS, IBM P6
TRANSISTOR COUNT
530
PAD OPENING SIZE:
90µm x 90µm
WAFER SIZE:
200mm (~8 inch)
14
FN6886.1
October 15, 2013
ISL3158AE
Metallization Mask Layout
ISL3158AE
VCC
RO
A
RE
B
Z
A
DE
DI
Y
G2
G1
For additional products, see www.intersil.com/en/products.html
Intersil products are manufactured, assembled and tested utilizing ISO9001 quality systems as noted
in the quality certifications found at www.intersil.com/en/support/qualandreliability.html
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time
without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be
accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
15
FN6886.1
October 15, 2013
ISL3158AE
Package Outline Drawing
M8.15
8 LEAD NARROW BODY SMALL OUTLINE PLASTIC PACKAGE
Rev 4, 1/12
DETAIL "A"
1.27 (0.050)
0.40 (0.016)
INDEX
6.20 (0.244)
5.80 (0.228)
AREA
0.50 (0.20)
x 45°
0.25 (0.01)
4.00 (0.157)
3.80 (0.150)
1
2
8°
0°
3
0.25 (0.010)
0.19 (0.008)
SIDE VIEW “B”
TOP VIEW
2.20 (0.087)
SEATING PLANE
5.00 (0.197)
4.80 (0.189)
1.75 (0.069)
1.35 (0.053)
1
8
2
7
0.60 (0.023)
1.27 (0.050)
3
6
4
5
-C-
1.27 (0.050)
0.51(0.020)
0.33(0.013)
SIDE VIEW “A
0.25(0.010)
0.10(0.004)
5.20(0.205)
TYPICAL RECOMMENDED LAND PATTERN
NOTES:
1. Dimensioning and tolerancing per ANSI Y14.5M-1994.
2. Package length does not include mold flash, protrusions or gate burrs.
Mold flash, protrusion and gate burrs shall not exceed 0.15mm (0.006
inch) per side.
3. Package width does not include interlead flash or protrusions. Interlead
flash and protrusions shall not exceed 0.25mm (0.010 inch) per side.
4. The chamfer on the body is optional. If it is not present, a visual index
feature must be located within the crosshatched area.
5. Terminal numbers are shown for reference only.
6. The lead width as measured 0.36mm (0.014 inch) or greater above the
seating plane, shall not exceed a maximum value of 0.61mm (0.024 inch).
7. Controlling dimension: MILLIMETER. Converted inch dimensions are not
necessarily exact.
8. This outline conforms to JEDEC publication MS-012-AA ISSUE C.
16
FN6886.1
October 15, 2013
Similar pages