IL3585
IsoLoop® is a registered trademark of NVE Corporation.
*U.S. Patent number 5,831,426; 6,300,617 and others.
REV. Q
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
High Speed Isolated RS-485 Transceivers
Functional Diagrams
DE
D
R
RE
ISODE
A
B
IL3585-3
XDE
(narrow-body)
DE
D
R
RE
ISODE
A
B
IL3585
(wide-body)
VID (A-B) DE RE R D Mode
≥ 200 mV L L H X Receive
≤−200 mV L L L X Receive
≥ 1.5 V H L H H Drive
≤−1.5 V H L L L Drive
X X H Z X Hi-Z R
Open L L H X Receive
Features
• 40 Mbps data rate
• 3 V to 5 V power supplies
• 20 ns propagation delay
• 5 ns pulse skew
• 50 kV/μs typ.; 30 kV/μs min. common mode transient immunity
• Low quiescent supply current
• 1000 VRMS/1500 VDC high voltage endurance
• 44000 year barrier life
• 15 kV bus ESD protection
• Low EMC footprint
• Thermal shutdown protection
• −40°C to +85°C temperature range
• Meets or exceeds ANSI RS-485 and ISO 8482:1987(E)
• UL 1577 recognized; IEC 60747-5-5 (VDE 0884) certified
• 0.15", 0.3", or True 8™ 16-pin SOIC packages
Applications
• Factory automation
• Industrial control networks
• Building environmental controls
• Equipment covered under IEC 61010-1 Edition 3
• 5 kVRMS rated IEC 60601-1 medical applications
Description
The IL3585 is a galvanically isolated, high-speed differential bus
transceiver, designed for bidirectional data communication on
balanced transmission lines. The device uses NVE’s patented*
IsoLoop spintronic Giant Magnetoresistance (GMR) technology.
A unique ceramic/polymer composite barrier provides excellent
isolation and virtually unlimited barrier life.
The part is available in an ultraminiature 0.15" 16-pin SOIC
package, a JEDEC-standard 0.3"-wide package, or NVE’s exclusive
True 8™ 16-pin SOIC package for true 8 millimeter creepage.
The IL3585 delivers an exceptional 2.3 V differential output into a
54 Ω load over the supply range of 4.5 V to 5.5 V. This provides
better data integrity over longer cable lengths, even at data rates as
high as 40 Mbps. The device is also compatible with 3 V supplies,
allowing interface to standard microcontrollers without additional
level shifting.
Current limiting and thermal shutdown features protect against
output short circuits and bus contention that may cause excessive
power dissipation. Receiver inputs feature a “fail-safe if open”
design, ensuring a logic high R-output if A/B are floating.
IL3585
2
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Absolute Maximum Ratings(11)
Parameter Symbol Min. Typ. Max. Units Test Conditions
Storage Temperature TS −55 150 °C
Junction Temperature TJ −55 150 °C
Ambient Operating Temperature TA −40 85 °C
Voltage Range at A or B Bus Pins −7 12 V
Supply Voltage
(
1
)
V
DD1, VDD2 −0.5 7 V
Digital Input Voltage −0.5 VDD + 0.5 V
Digital Output Voltage −0.5 VDD + 1 V
ESD (all bus nodes) 15 kV HBM
Recommended Operating Conditions
Parameter Symbol Min. Typ. Max. Units Test Conditions
Supply Voltage VDD1
VDD2
3.0
4.5 5.5
5.5 V
Junction Temperature TJ −40 110 °C
Input Voltage at any Bus Terminal
(separately or common mode)
VI
VIC
12
−7 V
High-Level Digital Input Voltage VIH 2.4
3.0 V
DD1 V
VDD1 = 3.3 V
VDD1 = 5.0 V
Low-Level Digital Input Voltage VIL 0 0.8 V
Differential Input Voltage
(
2
)
V
ID +12 / −7 V
High-Level Output Current (Driver) IOH 60 mA
High-Level Digital Output Current
(Receiver) IOH 8 mA
Low-Level Output Current (Driver) IOL −60 mA
Low-Level Digital Output Current
(Receiver) IOL −8 mA
Ambient Operating Temperature TA −40 85 °C
Digital Input Signal Rise and Fall Times tIR, tIF DC Stable
Insulation Specifications
Parameter Symbol Min. Typ. Max. Units Test Conditions
Creepage Distance
(external)
IL3585-3E
IL3585E 4.0
8.03
8.3 mm
Per IEC 60601
Total Barrier Thickness (internal) 0.012 0.013 mm
Barrier Resistance RIO >1014 Ω 500 V
Barrier Capacitance CIO 3 pF f = 1 MHz
Leakage Current 0.2 μARMS 240 VRMS, 60 Hz
Comparative Tracking Index CTI ≥175 V Per IEC 60112
High Voltage Endurance
(Maximum Barrier Voltage
for Indefinite Life)
AC
DC
VIO
1000
1500
VRMS
VDC
At maximum
operating temperature
Barrier Life 44000 Years 100°C, 1000 VRMS, 60%
CL activation energy
Thermal Characteristics
Parameter Symbol Min. Typ. Max. Units Test Conditions
Junction–Ambient
Thermal Resistance
IL3585-3E
IL3585E θJA 100
60 °C/W
Soldered to double-
sided board; free air;
case temperature
measured on top surface
Junction–Case
Thermal Resistance
IL3585-3E
IL3585E ΨJT 25
12 °C/W
Power Dissipation IL3585-3E
IL3585E PD
625
800 mW
IL3585
3
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Safety and Approvals
IEC 60747-5-5 (VDE 0884) (File Number 5016933-4880-0001)
• Working Voltage (VIORM) 600 VRMS (848 VPK); basic insulation; pollution degree 2
• Transient overvoltage (VIOTM) and surge voltage (VIOSM) 4000 VPK
• Each part tested at 1590 VPK for 1 second, 5 pC partial discharge limit
• Samples tested at 4000 VPK for 60 sec.; then 1358 VPK for 10 sec. with 5 pC partial discharge limit
IEC 61010-1 (Edition 2; TUV Certificate Numbers N1502812; N1502812-101)
Reinforced Insulation; Pollution Degree II; Material Group III
Part No. Suffix Package Working Voltage
-3 SOIC 150 VRMS
None Wide-body SOIC/True 8™ 300 VRMS
UL 1577 (Component Recognition Program File Number E207481)
Each part tested at 3000 VRMS (4240 VPK) for 1 second; each lot sample tested at 2500 VRMS (3530 VPK) for 1 minute
Soldering Profile
Per JEDEC J-STD-020C, MSL 1
IL3585
4
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
IL3585-3 (0.15" SOIC Package) Pin Connections
1 VDD1 Input power supply
2 GND1 Input power supply ground return
3 R Output data from bus
4
RE Read data enable
(if RE is high, R= high impedance)
5 D Data input to bus
6 DE Drive enable
7, 8, 9 NC No internal connection
10 XDE
Transceiver Device Enable input enables the
transceiver from the bus side, or is
connected to ISODE to enable the trans-
ceiver from the controller-side DE input.
(this input should not be left unterminated)
11 A Non-inverting bus line
12 B Inverting bus line
13 VDD2X Output transceiver power supply
(normally connected to pin 16)
14 ISODE
Isolated DE output
(normally connected to pin 10)
15 GND2 Output power supply ground return.
16 VDD2I Output isolation power supply
(normally connected to pin 13)
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
RE
VDD2I
GND1
DE
GND2
R ISODE
VDD2X
DB
A
XDE
NC
VDD1
NC
NC
IL3585-3
IL3585 (0.3" SOIC Package) Pin Connections
1 VDD1 Input power supply
2 GND1 Input power supply ground return
(pin 2 is internally connected to pin 8)
3 R Output data from bus
4
RE Read data enable
(if RE is high, R= high impedance)
5 DE Drive enable
6 D Data input to bus
7 NC No internal connection
8 GND1 Input power supply ground return
(pin 8 is internally connected to pin 2)
9 GND2 Output power supply ground return
(pin 9 is internally connected to pin 15)
10 ISODE
Isolated DE output for use in PROFIBUS
applications where the state of the isolated
drive enable node needs to be monitored.
11 NC No internal connection
12 A Non-inverting bus line
13 B Inverting bus line
14 NC No internal connection
15 GND2 Output power supply ground return
(pin 15 is internally connected to pin 9)
16 VDD2 Output power supply
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
RE
VDD
2
GND
1
D
GND
2
RNC
B
DE A
NC
ISODE
GND
1
VDD
1
GND
2
NC
IL3585
IL3585
5
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Driver Section
Electrical Specifications (Tmin to Tmax and VDD = 4.5 V to 5.5 V unless otherwise stated)
Parameter Symbol Min.
Typ.
(
5
)
Max. Units Test Conditions
Input Clamp Voltage VI
K
−1.5 V IL = −18 mA
Output voltage VO V
DD V IO = 0
Differential Output Voltage
(
2
)
|VOD1| VDD V IO = 0
Differential Output Voltage
(
2
)
|VOD2| 2.5 3 5 V RL = 54 Ω, VDD = 5 V
Differential Output Voltage
(
2, 6
)
VOD3 2.3 5 V RL = 54 Ω, VDD = 4.5 V
Change in Magnitude of Differential
Output Voltage(7) Δ|VOD| ±0.2 V RL = 54 Ω or 100 Ω
Common Mode Output Voltage VOC 3 V RL = 54 Ω or 100 Ω
Change in Magnitude of Common
Mode Output Voltage(7) Δ|VOC| ±0.2 V RL = 54 Ω or 100 Ω
Output Current(4) IO
1
−0.8 mA Output Disabled, VO = 12
V
O = −7
High Level Input Current IIH 10 μA VI = 3.5 V
Low Level Input Current IIL −10 μA VI = 0.4 V
Absolute |Short-circuit Output Current| IOS 250 mA −7 V < VO < 12 V
Supply Current VDD1 = 5 V
VDD1 = 3.3 V
IDD1
IDD1 4
3
6
4 mA No Load
(Outputs Enabled)
Notes (apply to both driver and receiver sections):
1. All voltages are with respect to network ground except differential I/O bus voltages.
2. Differential input/output voltage is measured at the noninverting terminal A with respect to the inverting terminal B.
3. Skew limit is the maximum propagation delay difference between any two devices at 25°C.
4. The power-off measurement in ANSI Standard EIA/TIA-422-B applies to disabled outputs only and is not applied to combined inputs and
outputs.
5. All typical values are at VDD1,VDD2 = 5 V or VDD1= 3.3 V and TA = 25°C.
6. −7 V < VCM < 12 V; 4.5 V < VDD < 5.5 V.
7. Δ|VOD| and Δ|VOC| are the changes in magnitude of VOD and VOC, respectively, that occur when the input is changed from one logic state to
the other.
8. This applies for both power on and power off, refer to ANSI standard RS-485 for exact condition. The EIA/TIA-422-B limit does not apply
for a combined driver and receiver terminal.
9. Includes 10 ns read enable time. Maximum propagation delay is 25 ns after read assertion.
10. Pulse skew is defined as |tPLH – tPHL| of each channel.
11. Absolute Maximum specifications mean the device will not be damaged if operated under these conditions. It does not guarantee
performance.
12. The relevant test and measurement methods are given in the Electromagnetic Compatibility section on p. 6.
13. External magnetic field immunity is improved by this factor if the field direction is “end-to-end” rather than to “pin-to-pin” (see diagram on p. 6).
IL3585
6
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Receiver Section
Electrical Specifications (Tmin to Tmax and VDD = 4.5 V to 5.5 V unless otherwise stated)
Parameter Symbol Min.
Typ.
(
5
)
Max. Units Test Conditions
Positive-going Input Threshold
Voltage VIT+ 0.2 V −7 V < VCM < 12 V
Negative-going Input Threshold
Voltage VIT− −0.2 V −7 V < VCM < 12 V
Hysteresis Voltage (VIT+ − VIT−) VHYS 40 mV VCM = 0 V, T = 25°C
High Level Digital Output Voltage VOH VDD – 0.2 VDD V
VID = 200 mV
IOH = −20 μA
Low Level Digital Output Voltage VOL 0.2 V
VID = −200 mV
IOH = 20 μA
High-impedance-state output current IOZ ±1 μA VO = 0.4 to (VDD2−0.5) V
Line Input Current
(
8
)
I
I 1 mA VI = 12 V
−0.8 mA VI = −7 V
Input Resistance RI 20 kΩ
Supply Current IDD2 5 16 mA
No load; Outputs
Enabled; VDD2X connected
to VDD2
I
if applicable
Switching Characteristics
VDD1 = 5 V, VDD2 = 5 V
Parameter Symbol Min.
Typ.
(
5
)
Max. Units Test Conditions
Data Rate 40 Mbps RL = 54 Ω, CL = 50 pF
Propagation Delay(2, 9) tPD 27 35 ns
VO = −1.5 to 1.5 V,
CL = 15 pF
Pulse Skew(2, 10) t
SK(P) 1 6 ns
VO = −1.5 to 1.5 V,
CL = 15 pF
Skew Limit
(
3
)
t
S
K
(LIM) 2 12 ns RL = 54 Ω, CL = 50 pF
Output Enable Time To High Level tPZH 15 25 ns CL = 15 pF
Output Enable Time To Low Level tPZL 15 25 ns CL = 15 pF
Output Disable Time From High Level tPHZ 15 25 ns CL = 15 pF
Output Disable Time From Low Level tPLZ 15 25 ns CL = 15 pF
Common Mode Transient Immunity
(Output Logic High to Logic Low) |CMH|,|CML| 30 50 kV/μs VCM = 1500 VDC
tTRANSIE
N
T = 25 ns
VDD1 = 3.3 V, VDD2 = 5 V
Parameter Symbol Min.
Typ.
(
5
)
Max. Units Test Conditions
Data Rate 40 Mbps RL = 54 Ω, CL = 50 pF
Propagation Delay(2, 9) tPD 30 38 ns
VO = −1.5 to 1.5 V,
CL = 15 pF
Pulse Skew(2, 10) t
SK(P) 1 6 ns
VO = −1.5 to 1.5 V,
CL = 15 pF
Skew Limit
(
3
)
t
S
K
(LIM) 4 12 ns RL = 54 Ω, CL = 50 pF
Output Enable Time To High Level tPZH 17 27 ns CL = 15 pF
Output Enable Time To Low Level tPZL 17 27 ns CL = 15 pF
Output Disable Time From High Level tPHZ 17 27 ns CL = 15 pF
Output Disable Time From Low Level tPLZ 17 27 ns CL = 15 pF
Common Mode Transient Immunity
(Output Logic High to Logic Low) |CMH|,|CML| 30 50 kV/μs VCM = 1500 VDC
tTRANSIENT = 25 ns
IL3585
7
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Magnetic Field Immunity(12)
VDD1 = 5 V, VDD2 = 5 V
Power Frequency Magnetic Immunity HPF 2800 3500 A/m 50Hz/60Hz
Pulse Magnetic Field Immunity HPM 4000 4500 A/m t
p
= 8µs
Damped Oscillatory Magnetic Field HOSC 4000 4500 A/m 0.1Hz – 1MHz
Cross-axis Immunity Multiplier
(
13
)
K
X 2.5
VDD1 = 3.3 V, VDD2 = 5 V
Power Frequency Magnetic Immunity HPF 1000 1500 A/m 50Hz/60Hz
Pulse Magnetic Field Immunity HPM 1800 2000 A/m t
p
= 8µs
Damped Oscillatory Magnetic Field HOSC 1800 2000 A/m 0.1Hz – 1MHz
Cross-axis Immunity Multiplier
(
13
)
K
X 2.5
IL3585
8
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Electrostatic Discharge Sensitivity
This product has been tested for electrostatic sensitivity to the limits stated in the specifications. However, NVE recommends that all integrated
circuits be handled with appropriate care to avoid damage. Damage caused by inappropriate handling or storage could range from performance
degradation to complete failure.
Narrow- and Wide-Body Pinout Differences
The narrow-body version (IL3585-3E) is designed for application flexibility and minimum board area in densely-populated PCAs. The wide-
body version (IL3585E) has redundant ground pins for layout flexibility.
The narrow-body version provides a separate isolated DE output (ISODE) and Transceiver Device Enable (XDE) input. ISODE follows the
Device Enable input (DE). XDE can be used to enable and disable the transceiver from the bus side, or connected to ISODE to enable and disable
the transceiver from the DE controller-side input. The narrow-body version also provides separate bus-side power supply pins—VDD2X for the
transceiver module and VDD2I for the isolation module. These pins should be externally connected for normal operation, but they can be used
separately for testing or troubleshooting.
The wide-body version has internal connections between the isolated DE output and the Transceiver Device Enable input, and well as between
the two VDD2 bus-side power supply pins. The two internally GND pins for each supply side provide layout flexibility. The ISODE output can be
used in PROFIBUS applications where the state of the isolated drive enable node needs to be monitored, or for testing or troubleshooting.
Dynamic Power Consumption
IsoLoop Isolators achieve their low power consumption from the way they transmit data across the isolation barrier. By detecting the edge
transitions of the input logic signal and converting these to narrow current pulses, a magnetic field is created around the GMR Wheatstone
bridge. Depending on the direction of the magnetic field, the bridge causes the output comparator to switch following the input logic signal.
Since the current pulses are narrow, about 2.5 ns, the power consumption is independent of mark-to-space ratio and solely dependent on
frequency. This has obvious advantages over optocouplers, which have power consumption heavily dependent on frequency and time.
Data Rate (Mbps) IDD1 IDD2
1 150 μA 150 μA
10 1.5 mA 1.5 mA
20 3 mA 3 mA
40 6 mA 6 mA
Table 2. Typical Dynamic Supply Currents.
Power Supply Decoupling
Both VDD1 and VDD2 must be bypassed with 47 nF ceramic capacitors. These should be placed as close as possible to VDD pins for proper
operation. Additionally, VDD2 should be bypassed with a 10 µF tantalum capacitor.
Maintaining Creepage
Creepage distances are often critical in isolated circuits. In addition to meeting JEDEC standards, NVE isolator packages have unique creepage
specifications. Standard pad libraries often extend under the package, compromising creepage and clearance. Similarly, ground planes, if used,
should be spaced to avoid compromising clearance. Package drawings and recommended pad layouts are included in this datasheet.
DC Correctness
The IL3585 incorporates a patented refresh circuit to maintain the correct output state with respect to data input. At power up, the bus outputs
will follow the Function Table shown on Page 1. The DE input should be held low during power-up to eliminate false drive data pulses from the
bus. An external power supply monitor to minimize glitches caused by slow power-up and power-down transients is not required.
IL3585
9
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Electromagnetic Compatibility
The IL3585 is fully compliant with generic EMC standards EN50081, EN50082-1 and the umbrella line-voltage standard for Information
Technology Equipment (ITE) EN61000. The IsoLoop Isolator’s Wheatstone bridge configuration and differential magnetic field signaling ensure
excellent EMC performance against all relevant standards. NVE conducted compliance tests in the categories below:
EN50081-1
Residential, Commercial & Light Industrial
Methods EN55022, EN55014
EN50082-2: Industrial Environment
Methods EN61000-4-2 (ESD), EN61000-4-3 (Electromagnetic Field Immunity), EN61000-4-4 (Electrical Transient Immunity),
EN61000-4-6 (RFI Immunity), EN61000-4-8 (Power Frequency Magnetic Field Immunity), EN61000-4-9 (Pulsed Magnetic
Field), EN61000-4-10 (Damped Oscillatory Magnetic Field)
ENV50204
Radiated Field from Digital Telephones (Immunity Test)
Immunity to external magnetic fields is even higher if the field direction is “end-to-end” (rather than to “pin-to-pin”) as shown in the diagram above.
IL3585
10
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Application Information
Figures 1a and 1b show typical connections to a microcontroller for the narrow-body and wide-body versions. The schematics include typical
termination and fail-safe resistors, and power supply decoupling capacitors:
12
11
VDD2 = 5 V
RFS-EXT
RT
RFS-EXT
120R
560R
560R
VDD1 = 3.3 V
ISODE
GND2GND1
47nF
CDD1
47nF
CDD2
10µF
C
DD2B
Isolation
Boundary
+
1
215
16
14
B
A
DE
D
R
RE
6
5
3
4
Microcontroller
XDE
10
13
IL3585-3
Figure 1a. Typical narrow-body connections.
13
12
R
FS-EXT
R
T
R
FS-EXT
120R
560R
560R
ISODE
GND2GND1
47nF
C
DD1
47nF
C
DD2
10µF
C
DD2B
Isolation
Boundary
IL3585
+
1
2 or 8 9 or 15
16
10
B
A
Microcontroller
DE
D
R
RE
5
6
3
4
VDD2 = 5 V
VDD1 = 3.3 V
Figure 1b. Typical wide-body connections.
Receiver Features
The receiver output “R” has tri-state capability via the active low RE input.
Driver Features
The RS-485 driver has a differential output and delivers at least 2.1 V across a 54 Ω load. Drivers feature low propagation delay skew to
maximize bit width and minimize EMI. Drivers have tri-state capability via the active-high DE input.
Receiver Data Rate, Cables and Terminations
The IL3585 is intended for networks up to 4,000 feet (1,200 m), but the maximum data rate decreases as cable length increases. Twisted pair
cable should be used in all networks since they tend to pick up noise and other electromagnetically induced voltages as common mode signals,
which are effectively rejected by the differential receiver.
IL3585
11
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Fail-Safe Operation
“Fail-safe operation” is defined here as the forcing of a logic high state on the “R” output in response to an open-circuit condition between the
“A” and “B” lines of the bus, or when no drivers are active on the bus.
Proper biasing can ensure fail-safe operation, that is a known state when there are no active drivers on the bus. IL3000-Series Isolated
Transceivers include internal pull-up and pull-down resistors of approximately 30 kΩ in the receiver section (RFS-INT; see figure below). These
internal resistors are designed to ensure failsafe operation but only if there are no termination resistors. The entire VDD will appear between inputs
“A” and “B” if there is no loading and no termination resistors, and there will be more than the required 200 mV with up to four RS-485 worst-
case Unit Loads of 12 kΩ. Many designs operating below 1 Mbps or less than 1,000 feet are unterminated. Termination resistors may not be
necessary for very low data rates and very short cable runs because reflections have time to settle before data sampling, which occurs at the
middle of the bit interval.
In busses with low-impedance termination resistors however, the differential voltage across the conductor pair will be close to zero with no active
drivers. In this case the state of the bus is indeterminate, and the idle bus will be susceptible to noise. For example, with 120 Ω termination
resistors (RT) on each end of the cable, and four Unit Loads (12 kΩ each), without external fail-safe biasing resistors the internal pull-up and pull-
down resistors will produce a voltage between inputs “A” and “B” of only about 5 mV. This is not nearly enough to ensure a known state.
External fail-safe biasing resistors (RFS-EXT) at one end of the bus can ensure fail-safe operation with a terminated bus. Resistors should be
selected so that under worst-case power supply and resistor tolerances there is at least 200 mV across the conductor pair with no active drivers to
meet the input sensitivity specification of the RS-485 standard.
Using the same value for pull-up and pull-down biasing resistors maintains balance for positive- and negative going transitions. Lower-value
resistors increase inactive noise immunity at the expense of quiescent power consumption. Note that each Unit Load on the bus adds a worst-case
loading of 12 kΩ across the conductor pair, and 32 Unit Loads add 375 Ω worst-case loading. The more loads on the bus, the lower the required
values of the biasing resistors.
In the example with two 120 Ω termination resistors and four Unit Loads, 560 Ω external biasing resistors provide more than 200 mV between
“A” and “B” with adequate margin for power supply variations and resistor tolerances. This ensures a known state when there are no active
drivers. Other illustrative examples are shown in the table below:
Fail-Safe Biasing
RB
V
DD
30K 30K
GND
A
5 V
R
FS-EXT
R
T
R
T
R
FS-EXT
R
FS-INT
R
FS-INT
Fail-Safe
RTLoadin
Operation?
None Four unit loads (12 kΩ ea.) 238 mV Yes
120 ΩFour unit loads (12 kΩ ea.) 5 mV No
560 Ω120 ΩFour unit loads (12 kΩ ea.) 254 mV Yes
510 Ω120 Ω32 unit loads (12 kΩ ea.) 247 mV Yes
Nominal VA-B
(inactive)
RFS -EXT
Internal Only
Internal Only
IL3585
12
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Package Drawings
0.15" 16-pin SOIC Package (-3 suffix)
0.386 (9.8)
0.394 (10.0)
0.049 (1.24)
0.051 (1.30)
0.007 (0.2)
0.013 (0.3)
Pin 1 identified
by either an
indent or a
marked dot
0.004 (0.1)
0.012 (0.3)
0.016 (0.4)
0.050 (1.3)
NOTE: Pin spacing is a BASIC
dimension; tolerances
do not accumulate
0.054 (1.4)
0.072 (1.8)
0.228 (5.8)
0.244 (6.2)
0.150 (3.81)
0.157 (3.99)
0.055 (1.40)
0.062 (1.58)
0.013 (0.3)
0.020 (0.5)
NOM
Dimensions in inches (mm); scale = approx. 5X
0.3" 16-pin SOIC Package (no suffix)
0.049 (1.24)
0.051 (1.30)
0.017 (0.43)*
0.022 (0.56)
0.292 (7.42)*
0.299 (7.59)
0.007 (0.18)*
0.010 (0.25)
0.260 (6.60)*
0.280 (7.11)
0.033 (0.85)*
0.043 (1.10)
0.007 (0.2)
0.013 (0.3)
Pin 1 identified by
either an indent
or a marked dot 0.08 (2.0)
0.10 (2.5)
0.397 (10.08)
0.413 (10.49)
0.394 (10.00)
0.419 (10.64)
0.092 (2.34)
0.105 (2.67)
0.004 (0.1)
0.012 (0.3)
0.016 (0.4)
0.050 (1.3)
NOTE: Pin spacing is a BASIC
dimension; tolerances
do not accumulate
0.013 (0.3)
0.020 (0.5)
Dimensions in inches (mm); scale = approx. 5X
*Specified for True 8™ package to guarantee 8 mm creepage per IEC 60601.
IL3585
13
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Recommended Pad Layouts
0.15" 16-pin SOIC Pad Layout
0.050 (1.27)
0.275 (6.99)
0.020 (0.51)
16 PLCS
0.160 (4.06)
Dimensions in inches (mm); scale = approx. 5X
0.3" 16-pin SOIC Pad Layout
0.050 (1.27)
0.449 (11.40)
0.020 (0.51)
16 PLCS
0.317 (8.05)
Dimensions in inches (mm); scale = approx. 5X
IL3585
14
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Ordering Information and Valid Part Numbers
IL 35 85 -3 E TR13
Bulk Packaging
Blank = Tube
TR13 = 13'' Tape and Reel
Package
E = RoHS Compliant
Package Type
Blank = 0.3'' SOIC
-3 = 0.15'' SOIC
Channel Configuration
85 = RS-485
Base Part Number
35 = Digital-In, 40 Mbps Transceiver
Product Family
IL = Isolators
Valid Part Numbers
IL3585E
IL3585E TR13
IL3585-3E
IL3585-3E TR13
RoHS
COMPLIANT
IL3585
15
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Revision History
ISB-DS-001-IL3585-Q
December 2013
Change
• IEC 60747-5-5 (VDE 0884) certification.
• Upgraded from MSL 2 to MSL 1.
ISB-DS-001-IL3585-P
Change
• Increased transient immunity specifications based on additional data.
• Added VDE 0884 pending.
• Added transient immunity specifications.
• Added high voltage endurance specification.
• Increased magnetic immunity specifications.
• Updated package drawings.
• Added recommended solder pad layouts.
ISB-DS-001-IL3585-O
Change
• Added thermal characteristics (p. 2).
• Cosmetic changes.
ISB-DS-001-IL3585-N
Change
• Added narrow-body version (IL3585-3E).
• Detailed isolation and barrier specifications.
• Added application schematics (p. 7).
ISB-DS-001-IL3585-M
Change
• Update terms and conditions.
ISB-DS-001-IL3585-L
Change
• Revised maximum Receiver Section Supply Current to 16 mA.
ISB-DS-001-IL3585-K
Change
• Added low EMC footprint.
ISB-DS-001-IL3585-J
Change
• Added bus-protection ESD specification (15 kV).
IL3585
16
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Datasheet Limitations
The information and data provided in datasheets shall define the specification of the product as agreed between NVE and its customer, unless NVE and
customer have explicitly agreed otherwise in writing. All specifications are based on NVE test protocols. In no event however, shall an agreement be
valid in which the NVE product is deemed to offer functions and qualities beyond those described in the datasheet.
Limited Warranty and Liability
Information in this document is believed to be accurate and reliable. However, NVE does not give any representations or warranties, expressed or
implied, as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information.
In no event shall NVE be liable for any indirect, incidental, punitive, special or consequential damages (including, without limitation, lost profits, lost
savings, business interruption, costs related to the removal or replacement of any products or rework charges) whether or not such damages are based on
tort (including negligence), warranty, breach of contract or any other legal theory.
Right to Make Changes
NVE reserves the right to make changes to information published in this document including, without limitation, specifications and product descriptions
at any time and without notice. This document supersedes and replaces all information supplied prior to its publication.
Use in Life-Critical or Safety-Critical Applications
Unless NVE and a customer explicitly agree otherwise in writing, NVE products are not designed, authorized or warranted to be suitable for use in life
support, life-critical or safety-critical devices or equipment. NVE accepts no liability for inclusion or use of NVE products in such applications and such
inclusion or use is at the customer’s own risk. Should the customer use NVE products for such application whether authorized by NVE or not, the
customer shall indemnify and hold NVE harmless against all claims and damages.
Applications
Applications described in this datasheet are illustrative only. NVE makes no representation or warranty that such applications will be suitable for the
specified use without further testing or modification.
Customers are responsible for the design and operation of their applications and products using NVE products, and NVE accepts no liability for any
assistance with applications or customer product design. It is customer’s sole responsibility to determine whether the NVE product is suitable and fit for
the customer’s applications and products planned, as well as for the planned application and use of customer’s third party customers. Customers should
provide appropriate design and operating safeguards to minimize the risks associated with their applications and products.
NVE does not accept any liability related to any default, damage, costs or problem which is based on any weakness or default in the customer’s
applications or products, or the application or use by customer’s third party customers. The customer is responsible for all necessary testing for the
customer’s applications and products using NVE products in order to avoid a default of the applications and the products or of the application or use by
customer’s third party customers. NVE accepts no liability in this respect.
Limiting Values
Stress above one or more limiting values (as defined in the Absolute Maximum Ratings System of IEC 60134) will cause permanent damage to the
device. Limiting values are stress ratings only and operation of the device at these or any other conditions above those given in the recommended
operating conditions of the datasheet is not warranted. Constant or repeated exposure to limiting values will permanently and irreversibly affect the
quality and reliability of the device.
Terms and Conditions of Sale
In case an individual agreement is concluded only the terms and conditions of the respective agreement shall apply. NVE hereby expressly objects to
applying the customer’s general terms and conditions with regard to the purchase of NVE products by customer.
No Offer to Sell or License
Nothing in this document may be interpreted or construed as an offer to sell products that is open for acceptance or the grant, conveyance or implication
of any license under any copyrights, patents or other industrial or intellectual property rights.
Export Control
This document as well as the items described herein may be subject to export control regulations. Export might require a prior authorization from national authorities.
Automotive Qualified Products
Unless the datasheet expressly states that a specific NVE product is automotive qualified, the product is not suitable for automotive use. It is neither
qualified nor tested in accordance with automotive testing or application requirements. NVE accepts no liability for inclusion or use of non-automotive
qualified products in automotive equipment or applications.
In the event that customer uses the product for design-in and use in automotive applications to automotive specifications and standards, customer (a) shall
use the product without NVE’s warranty of the product for such automotive applications, use and specifications, and (b) whenever customer uses the
product for automotive applications beyond NVE’s specifications such use shall be solely at customer’s own risk, and (c) customer fully indemnifies
NVE for any liability, damages or failed product claims resulting from customer design and use of the product for automotive applications beyond NVE’s
standard warranty and NVE’s product specifications.
IL3585
17
NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
An ISO 9001 Certified Company
NVE Corporation
11409 Valley View Road
Eden Prairie, MN 55344-3617 USA
Telephone: (952) 829-9217
Fax: (952) 829-9189
www.nve.com
e-mail: iso-info@nve.com
©NVE Corporation
All rights are reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner.
ISB-DS-001-IL3585-Q
November 2013