IL422

Isolated RS422/RS485 Interface

Functional Diagram Features
• 3.3 V Input Supply Compatible
• 2500 Vrms Isolation (1 min.)
• 25 ns Maximum Propagation Delay
DE ISODE
• 25 Mbps Data Rate
• 1 ns Pulse Skew (typ.)
D Y • ±60 mA Driver Output Capability
Z • Thermal Shutdown Protection
A • Meets or Exceeds ANSI 422-B, EIA 485-A and
R ITU Recommended V11
B
• −40°C to +85°C Temperature Range
RE • PROFIBUS International Component Recognition
• 16-pin SOIC Package
IL422 • UL1577 and IEC 61010-2001 Approval

IL422 Receiver IL422 Driver Applications

RE R V(A−B) DE D V(Y−Z) Multi-point or multi-drop transmission on long bus lines in noisy
H Z X L X Z environments.
L H ≥ 200 mV H H ≥ 200 mV
L L ≤−200 mV H L ≤−200 mV
L I Open Description
The IL422 is a galvanically isolated, high-speed differential bus
H = High Level, L = Low Level transceiver, designed for bidirectional data communication on
I = Indeterminate, X = Irrelevant, Z = High Impedance balanced transmission lines. The devices use NVE’s patented*
IsoLoop spintronic Giant Magnetoresistance (GMR) technology. The
IL422 is the first isolated RS-422 interface in a standard 16-pin
SOIC package that meets the ANSI Standards EIA/TIA-422-B and
RS-485 and is compatible with 3.3V input supplies.
The IL422 has current limiting and thermal shutdown features to
protect against output short circuits and bus contention situations that
could cause excessive power dissipation.

Isoloop is a registered trademark of NVE Corporation. REV. M

*U.S. Patent number 5,831,426; 6,300,617 and others.

NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©2007 NVE Corporation
 IL422
Absolute Maximum Ratings(11)
Parameters Symbol Min. Typ. Max. Units Test Conditions
Storage Temperature TS −65 150 °C
Ambient Operating Temperature TA −40 100 °C
Voltage Range at A or B Bus Pins −7 12 V
Supply Voltage(1) VDD1, VDD2 −0.5 7 V
Digital Input Voltage −0.5 5.5 V
Digital Output Voltage −0.5 VDD + 1 V
725 25°C
Continuous Total Power Dissipation mW
377 85°C
Maximum Output Current IO 95 mA
Lead Solder Temperature 260 °C 10 sec.
ESD 2 kV HBM

Recommended Operating Conditions

Parameters Symbol Min. Typ. Max. Units Test Conditions
VDD1 3.0 5.5
Supply Voltage V
VDD2 4.5 5.5
Input Voltage at any Bus Terminal VI 12
V
(separately or common mode) VIC −7
2.4 VDD1 = 3.3 V
High-Level Digital Input Voltage VIH VDD1 V
3.0 VDD1 = 5.0 V
Low-Level Digital Input Voltage VIL 0 0.8 V
Differential Input Voltage(2) VID ±12 V
High-Level Output Current (Driver) IOH 60 mA
High-Level Digital Output Current
IOH 8 mA
(Receiver)
Low-Level Output Current (Driver) IOL −60 mA
Low-Level Digital Output Current
IOL −8 mA
(Receiver)
Ambient Operating Temperature TA −40 85 °C
Transient Immunity 20 kV/μs
Digital Input Signal
tIR,tIF DC Stable
Rise and Fall Times

Insulation Specifications
Parameters Symbol Min. Typ. Max. Units Test Conditions
Creepage Distance 8.08 mm
Barrier Impedance >1014||7 Ω || pF
Leakage Current 0.2 μA 240 VRMS, 60 Hz

Safety and Approvals

IEC61010-1
TUV Certificate Numbers: N1502812, N1502812-101
Classification: Reinforced Insulation
Model Package Pollution Degree Material Group Max. Working Voltage
IL422 0.3" SOIC II III 300 VRMS

UL 1577
Component Recognition Pprogram File Number: E207481
Rated 2500VRMS for 1 minute
Soldering Profile
Per JEDEC J-STD-020C, MSL=2

NVE Corporation 11409 Valley View Road Eden Prairie, MN 55344-3617 USA Telephone: (952) 829-9217 Fax (952) 829-9189 Internet: www.isoloop.com
 IL422
IL422 Pin Connections
1 VDD1 Input Power Supply
2 GND1 Input Power Supply Ground Return
3 R Output Data from Bus
VDD1 VDD2
Read Data Enable
4 RE
(if RE is high, R = high impedance) GND1 GND2
5 DE Drive Enable R A
6 D Data Input to Bus
7 NC No Internal Connection RE B

8 GND1 Input Power Supply Ground Return DE Z

9 GND2 Output Power Supply Ground Return
D Y
Isolated DE Output for use in Profibus
10 ISODE applications where the state of the isolated NC ISODE
drive enable node needs to be monitored
GND1 GND2
11 Y Y Bus (Drive – True)
12 Z Z Bus (Drive – Inverse) IL422
13 B B Bus (Receive – Inverse)
14 A A Bus (Receive – True)
15 GND2 Output Power Supply Ground Return
16 VDD2 Output Power Supply

NVE Corporation 11409 Valley View Road Eden Prairie, MN 55344-3617 USA Telephone: (952) 829-9217 Fax (952) 829-9189 Internet: www.isoloop.com
 IL422
Driver Section
Electrical specifications are Tmin to Tmax and VDD = 4.5 V to 5.5 V unless otherwise stated.
Parameters Symbol Min. Typ.(5) Max. Units Test Conditions
Input Clamp Voltage VIK −1.5 V IL = −18 mA
Output voltage VO 0 6 V IO = 0
Differential Output Voltage(2) |VOD1| 1.5 6 V IO = 0
Differential Output Voltage(2) |VOD2| 1.5 2.5 5 V RL = 54 Ω, VDD = 5 V
Differential Output Voltage(2)(6) VOD3 1.5 5 V RL = 54 Ω, VDD = 4.5 V
Change in Magnitude of Differential
Δ|VOD| ±0.2 V RL = 54 Ω or 100 Ω
Output Voltage(7)
3
Common Mode Output Voltage VOC V RL = 54 Ω or 100 Ω
−1
Change in Magnitude of Common
Δ|VOC| ±0.2 V RL = 54 Ω or 100 Ω
Mode Output Voltage(7)
1 VO = 12 V
Output Current(4) Output Disabled IO mA
−0.8 VO = −7 V
High Level Input Current IIH 10 μA VI = 3.5 V
Low Level Input Current IIL −10 μA VI = 0.4 V
250 VO = −6 V
Short-circuit Output Current IOS −150 mA VO = 0 V
−250 VO = 8 V
VDD1 = +5 V IDD1 4 6 No Load
Supply Current mA
VDD1 = +3.3 V IDD1 3 3 (Outputs Enabled)
Switching Specifications
Parameters Symbol Min. Typ.(5) Max. Units Test Conditions
Maximum Data Rate 25 Mbps RL = 54 Ω, CL = 50 pF
Differential Output Prop Delay tD(OD) 16 25 ns RL = 54 Ω, CL = 50 pF
Pulse Skew(10) tS(P) 1 6 ns RL = 54 Ω, CL = 50 pF
Differential Output Rise & Fall Time tT(OD) 8 10 ns RL = 54 Ω, CL = 50 pF
Output Enable Time to High Level tPZH 31 65 ns RL = 54 Ω, CL = 50 pF
Output Enable Time to Low Level tPZL 22 35 ns RL = 54 Ω, CL = 50 pF
Output Disable Time from High Level tPHZ 28 50 ns RL = 54 Ω, CL = 50 pF
Output Disable Time from Low Level tPLZ 16 32 ns RL = 54 Ω, CL = 50 pF
Skew Limit(3) tSK(LIM) 2 8 ns RL = 54 Ω, CL = 50 pF

Notes (apply to both driver and receiver sections):

1. All voltage values 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. The minimum VOD2 with a 100 Ω load is either ½ VOD1 or 2 V, whichever is greater.
7. Δ|VOD| and Δ|VOC| are the changes in magnitude of VOD and VOC, respectively,
that occur when the input is changed form 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 8 ns read enable time. Maximum propagation delay is 25 ns after read assertion.
10. Pulse skew is defined as |tPLH − tPHL| of each channel.

NVE Corporation 11409 Valley View Road Eden Prairie, MN 55344-3617 USA Telephone: (952) 829-9217 Fax (952) 829-9189 Internet: www.isoloop.com
 IL422
Receiver Section
Electrical specifications are Tmin to Tmax and VDD = 4.5 V to 5.5 V unless otherwise stated.
Parameters Symbol Min. Typ.(5) Max. Units Test Conditions
Positive-going Input VO = 2.7 V,
VIT+ 0.2 V
Threshold Voltage IO = −0.4 mA
Negative-going Input VO = 0.5 V,
VIT- −0.2 V
Threshold Voltage IO = 8 mA
Hysteresis Voltage (VIT+ − VIT-) VHYS 60 mV
VID = 200 mV
High Level Digital Output Voltage VOH VDD − 0.2 V
IOH = −20 μA
VID = −200 mV
Low Level Digital Output Voltage VOL 0.2 V
IOH = 20 μA
High-impedance-state output current IOZ ±10 μA VO = 0.4 to (VDD2−0.5) V
VI = 12 V
1
Line Input Current(8) II mA VI = −7 V
−0.8
Other Input(11) = 0 V
Input Resistance rI 12 20 kΩ
No load
Supply Current IDD2 27 34 mA
Outputs Enabled
Switching Characteristics at 5 V
Parameters Symbol Min. Typ.(5) Max. Units Test Conditions
Maximum Data Rate 25 Mbps RL = 54 Ω, CL = 50 pF
VO = −1.5 V to 1.5 V,
Propagation Delay(9) tPD 24 32 ns
CL = 15 pF
VO = −1.5 V to 1.5 V,
Pulse Skew(10) tSK(P) 1 6 ns
CL = 15 pF
(3)
Skew Limit tSK(LIM) 2 8 ns RL = 54 Ω, CL = 50 pF
Output Enable Time To High Level tPZH 17 24 ns CL = 15 pF
Output Enable Time To Low Level tPZL 30 45 ns CL = 15 pF
Output Disable Time From High Level tPHZ 30 45 ns CL = 15 pF
Output Disable Time From Low Level tPLZ 18 27 ns CL = 15 pF
Switching Characteristics at 3.3 V
Parameters Symbol Min. Typ.(5) Max. Units Test Conditions
Maximum Data Rate 25 Mbps RL = 54 Ω, CL = 50 pF
VO = −1.5 V to 1.5 V,
Propagation Delay(9) tPD 27 32 ns
CL = 15 pF
VO = −1.5 V to 1.5 V,
Pulse Skew(10) tSK(P) 2 6 ns
CL = 15 pF
(3)
Skew Limit tSK(LIM) 4 8 ns RL = 54 Ω, CL = 50 pF
Output Enable Time To High Level tPZH 20 24 ns CL = 15 pF
Output Enable Time To Low Level tPZL 33 45 ns CL = 15 pF
Output Disable Time From High Level tPHZ 33 45 ns CL = 15 pF
Output Disable Time From Low Level tPLZ 20 27 ns CL = 15 pF

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.

NVE Corporation 11409 Valley View Road Eden Prairie, MN 55344-3617 USA Telephone: (952) 829-9217 Fax (952) 829-9189 Internet: www.isoloop.com
 IL422
Application Information
Dynamic Power Consumption Power Supply Decoupling
IsoLoop Isolators achieve their low power consumption from the Low ESR capacitors such as ceramic are required to decouple the
way they transmit data across the isolation barrier. By detecting the supplies. Both VDD1 and VDD2 must be bypassed with 47 nF
edge transitions of the input logic signal and converting these to capacitors. These should be placed as close as possible to VDD pins
narrow current pulses, a magnetic field is created around the GMR for proper operation. Additionally, V DD2 should have a 10 µF
Wheatstone bridge. Depending on the direction of the magnetic tantalum capacitor connected in parallel with the 47 nF capacitor.
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.
The approximate power supply current per channel is:

IIN = 40 x f x 1 mA
fMAX 4

Where f = operating frequency

fMAX = 50 MHz

NVE Corporation 11409 Valley View Road Eden Prairie, MN 55344-3617 USA Telephone: (952) 829-9217 Fax (952) 829-9189 Internet: www.isoloop.com
 IL422
0.3" 16-pin SOIC Package
Dimensions in inches (mm)
0.287 (7.29)
0.300 (7.62)
0.013 (0.3)
0.020 (0.5) NOM

0.397 (10.08) 0.007 (0.2) 0.016 (0.4)

0.413 (10.50) 0.013 (0.3) 0.050 (1.3)

0.092 (2.34)
Pin 1 identified by
0.105 (2.67)
either an indent
or a marked dot 0.08 (2.0)
0.10 (2.5)

0.040 (1.0)
0.394 (10.00) 0.004 (0.1)
0.060 (1.5)
0.419 (10.64) 0.012 (0.3)

Ordering Information and Valid Part Numbers

IL 422 E TR13
Bulk Packaging Valid Part Numbers
Blank = Tube IL422
TR = 13'' Tape and Reel IL422E

Package All IL422

Blank = 80/20 Tin/Lead Plating part types are
E = RoHS Compliant available on
tape and reel.
Base Part Number
422 = RS-422 Transceiver

Product Family
IL = Isolators

RoHS
COMPLIANT

NVE Corporation 11409 Valley View Road Eden Prairie, MN 55344-3617 USA Telephone: (952) 829-9217 Fax (952) 829-9189 Internet: www.isoloop.com
 IL422

ISB-DS-001-IL422-M Changes
September 2007 • Changed ordering information to reflect that devices are now fully RoHS compliant with
no exemptions.
ISB-DS-001-IL422-L Changes
• Reorganized supply current specifications; misc. minor changes

ISB-DS-001-IL422-K Changes
• Eliminated soldering profile chart

ISB-DS-001-IL422-J Changes
• Updated open input state in truth table

ISB-DS-001-IL422-I Changes
• Updated package drawing; misc.

ISB-DS-001-IL422-H Changes
• Updated UL and IEC approvals

ISB-DS-001-IL422-G Changes
• Revision letter added.
• Ordering Information Removed.
• IEC 61010-1 Classification: “Reinforced Insulation” added.
• Notes added.
• IR Soldering Profile added
• Ordering Information added.

NVE Corporation 11409 Valley View Road Eden Prairie, MN 55344-3617 USA Telephone: (952) 829-9217 Fax (952) 829-9189 Internet: www.isoloop.com
 IL422

About NVE

An ISO 9001 Certified Company

NVE Corporation manufactures innovative products based on unique spintronic Giant Magnetoresistive (GMR) technology. Products include
Magnetic Field Sensors, Magnetic Field Gradient Sensors (Gradiometers), Digital Magnetic Field Sensors, Digital Signal Isolators, and Isolated
Bus Transceivers.
NVE pioneered spintronics and in 1994 introduced the world’s first products using GMR material, a line of ultra-precise magnetic sensors for
position, magnetic media, gear speed and current sensing.
NVE Corporation
11409 Valley View Road
Eden Prairie, MN 55344-3617 USA
Telephone: (952) 829-9217
Fax: (952) 829-9189
Internet: www.nve.com
e-mail: isoinfo@nve.com

The information provided by NVE Corporation is believed to be accurate. However, no responsibility is assumed by NVE Corporation for its use,
nor for any infringement of patents, nor rights or licenses granted to third parties, which may result from its use. No license is granted by
implication, or otherwise, under any patent or patent rights of NVE Corporation. NVE Corporation does not authorize, nor warrant, any NVE
Corporation product for use in life support devices or systems or other critical applications, without the express written approval of the
President of NVE Corporation.

Specifications shown are subject to change without notice.

ISB-DS-001-IL422-M
September 2007

NVE Corporation 11409 Valley View Road Eden Prairie, MN 55344-3617 USA Telephone: (952) 829-9217 Fax (952) 829-9189 Internet: www.isoloop.com