Isolated RS485 Interface. Features 2500 V RMS. Applications. Description

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1 NVE COPOATION IL485ISOLOOP Isolated S485 Interface Functional iagram Features GALVANIC ISOLATION ISO A B 2500 V MS Isolation (1 min) 25 ns Maximum Propagation elay 35 MBaud ata ate 1 ns Skew esigned for Multi-point Transmission on Long Bus Lines in Noisy Environments ±60 ma river Output Capability Thermal Shutdown Protection Meets or Exceeds ANSI S-485 and ISO 8482:1987 (E) -40 C to +85 C Temperature ange 16 Pin SOIC Package UL1577 Approved (File # E207481) Function Table Applications V I (A-B) E ISO MO 0.2V L L L H X eceive 0.2V L L L L X eceive -7<V I <12 X H X Z X eceive/rive 1.5 H L H H H rive 1.5 H L H L L rive Open L L L H X eceive H= High Level, L= Low Level, X= Irrelevant, Z= High Impedance POFIBUS/S485 S-485 Systems Multiple ata Point Transmission escription The IL485 is a galvanically isolated, high speed differential bus transceiver, designed for bidirectional data communication on balanced transmission lines. Isolation is achieved through patented* Isoloop technology. The IL485 is the first isolated S-485 interface available in a standard 16 pin SOIC package, which meets the ANSI Standards EIA/TIA-422-B and S485. The IL485 has current limiting and thermal shutdown features to protect against output short circuits and bus contention situations where these may cause excessive power dissipation. With a 6 nsec pulse skew and 25 nsec propagation delay, the IL485 is ideal for POFIBUS applications. Isoloop is a registered trademark of NVE, Inc. * US Patent number 5,831,426 and others

2 Absolute Maximum atings Parameters Symbol Min. Max. Units Storage Temperature T S o C Ambient Operating Temperature T A o C Voltage ange at A or B Bus Pins Volts Supply Voltage (1) V 1, V Volts igital Input Voltage Volts igital Output Voltage -0.5 V Volts Continuous Total Power issipation 725 mwatts (25 C) 377 mwatts (85 C) Maximum Output Current I O 95 mamps Lead Solder Temperature (10s) 260 C ES 2kV Human Body Model Insulation Specifications Parameter Condition Min. Typ. Max. Units ated Voltage, 1 min 2500 V MS Partial ischarge, 100% Tested (3) 1s,5pC 2000 V MS Creepage istance (External) mm Barrier Impedance > Ω pf Leakage Current 240 V MS 0.1 µamps 60Hz ecommended Operating Conditions Parameters Symbol Min. Max. Units Supply Voltage V 1,V Volts Input Voltage at any bus terminal V I 12 Volts (separately or common mode) VIC -7 High-level igital Input Voltage V IH 3 Volts Low-Level igital Input Voltage V IL 0.8 Volts ifferential Input Voltage (2) V I +12/-7 Volts High-Level Output Current (river) I OH -60 ma High-Level igital Output Current (eceiver) I OH 8 ma Low-Level Output Current (river) I OL 60 ma Low-Level igital Output Current (eceiver) I OL 8 ma Operating Free Air Temperature T A C Input Signal ise and Fall Times ( & only) t I,t IF 1 µsec 2

3 river Section All Specifications are T min to T max unless otherwise stated. Parameter Symbol Min. Typ. (5) Max. Units Test Conditions Input Clamp Voltage V IK -1.5 V I L =-18mA Output Voltage V O 0 6 V I O =0 ifferential Output Voltage V O V I O =0 ifferential Output Voltage (6) V O2 1/2 V O V L =100Ω or V L =54Ω ifferential Output Voltage V O V V test =-7 to 12V Change in Magnitude of (7) V O ±0.2 V ifferential Output Voltage L =54 or 100Ω Common Mode Output Voltage V OC 3 V L =54 or 100Ω -1 Change in Magnitude of (7 ) V OC ±0.2 V Common Mode Output Voltage L =54 or 100Ω Output Current (4) I O 1 ma Output isabled V O = ma V O =-7 High Level Input Current I IH 10 µa V 1 =3.5 V Low Level Input Current I IL -10 µa V 1 =0.4 V Short-Circuit Output Current I OS -250 ma V O = V O = V O = 8 Supply Current (V 2 = +5V) I ma No Load (Outputs Enabled) (V 1 = +5V) I ma Switching Characteristics Parameter Symbol Min. Typ. (5) Max. Units Test Conditions ata ate 35 Mbd L ifferential Output elay Time t (O) ns L Pulse Skew (10) t SK(P) 1 6 ns L ifferential Output Transition Time t T (O) 8 10 ns L Output Enable Time To High Level t PZH ns L Output Enable Time To Low Level t PZL ns L Output isable Time From High Level t PHZ ns L Output isable Time From Low Level t PLZ ns L Skew Limit (11) t SK (LIM) 2 8 ns L 3

4 eceiver Section All Specifications are T min to T max unless otherwise stated. Parameter Symbol Min. Typ. (5) Max. Units Test Conditions Positive-going Input Threshold Voltage V IT+ 0.2 V V O = 2.7V, I o = - 0.4mA Negative-going Input Threshold Voltage V IT- 0.2 V V O = 0.5V, I o = 8mA Hysteresis Voltage (V IT+ -V IT-) V hys 60 mv High Level igital Output Voltage V OH V 0.2 V V I = 200mV, I OH = -20µA Low Level igital Output Voltage V OL 0.2 V V I = -200mV, I OL =20µA High-impedance-state output current I OZ ±20 µa V O = 0.4 to (V 2-0.5) V Line Input Current (8) I I 1 ma Other Input (11) =0V V I =12V -0.8 V I = 7V Input esistance r i 50 kω Supply Current (V 2 = +5) I ma No Load (Outputs Enabled) (V 1 = +5) I ma Switching Characteristics Parameter Symbol Min. Typ. (5) Max. Units Test Conditions ata ate 35 Mbd L Propagation Time (9) t P ns V O =-1.5 to 1.5V, C L =15pF Pulse Skew (10) t SK(P) 1 6 ns V O =-1.5 to 1.5V, C L =15pF Skew Limit (11) t SK(lim) 2 8 ns L Output Enable Time To High Level t PZH ns C L =15pF Output Enable Time To Low Level t PZL ns C L =15pF Output isable Time From High Level t PHZ ns C L =15pF Output isable Time From Low Level t PLZ ns C L =15pF Electrostatic ischarge 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. amage caused by inappropriate handling or storage could range from performance degradation to complete failure. 4

5 Notes: 1. All Voltage values are with respect to network ground except differential I/O bus voltages. 2. ifferential input/output voltage is measured at the noninverting terminal A with respect to the inverting terminal B. 3. All devices receive a one second test. Failure criteria is 5 pulses of 5 pc. 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 V 1, V 2 = 5V and T A = 25 C. 6. The minimum V O2 with a 100Ω load is either 1/2V O1 or 2V, whichever is greater. 7. V O and V OC are the changes in magnitude of V O and V OC, 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 S-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 the t PLH -t PHL of each channel. 11. Skew limit is the maximum difference in any two channels in one device. Application Notes: Power Consumption The IL485 achieves its low power consumption from the manner by which it transmits data across its isolation barrier. By detecting the edge transitions of the input logic signal and converting this to a narrow current pulse which drives the isolation barrier, the isolator then latches the input logic state in the output latch. Since the current pulses are narrow, about 2.5 ns wide, the power consumption is independent of mark-to-space ratio and solely dependent on frequency. This has obvious advantages over optocouplers whose power consumption is heavily dependent on its on state and frequency. Power Supplies It is recommended that low ES ceramic capacitors be used to decouple the supplies. Both V 1 and V 2 should be bypassed with 47 nf capacitors. These should be placed no further than 1 cm from the device pins for proper operation. In addition, V 2 should have a 10 µf tantalum capacitor connected in parallel with the 47 nf capacitor. 5

6 Pin Configuration V 1 V 2 V V 2 GN 1 E n\c GN 2 n\c B A n\c ISO E GALVANIC ISOLATION ISO A B GN GN 2 GN 1 GN 2 Pin escription Pin Mnemonic escription 1 V 1 Input Power Supply 2 GN 1 Input Power Supply Ground eturn 3 Output ata from Bus If is High, is input data If is Low, is Bus (A-B) data 4 E ead ata Enable 5 rive Enable 6 ata Input to Bus 7 n\c No Internal Connection 8 GN 1 Input Power Supply Ground eturn 9 GN 2 Output Power Supply Ground eturn 10 ISO Isolated Output for use in Profibus applications where the state of the drive enable node needs to be monitored 11 n\c No Internal Connection 12 A A Bus Connection to S485 (True) 13 B B Bus Connection to S485 (Inverse) 14 n\c No Internal Connection 15 GN 2 Output Power Supply eturn 16 V 2 Output Power Supply 6

7 IL485 (Wide Body SOIC-16 Package) 0.397(10.084) 0.413(10.490) Pin 1 Indent 8 1 imensions in inches (mm) (10.007) (10.643) (7.391) 0.299(7.595) 7 0 TYP 0.287(7.290) 0.297(7.544) 0.010(0.254) 0.020(0.508) x TYP 7 0 TYP 0.013(0.330) 0.020(0.508) 0.009(0.229) 0.012(0.305) 0.092(2.337) 0.104(2.642) 0.016(0.41) 0.050(1.27) 0.080(2.032) 0.100(2.54) 0.040(1.016) 0.060(1.524) 0.004(0.1016) 0.011(0.279) 7

8 About NVE An ISO 9001 Certified Company NVE Corporation is a high technology components manufacturer having the unique capability to combine leading edge Giant Magnetoresistive (GM) materials with integrated circuits to make novel electronic components. Products include Magnetic Field Sensors, Magnetic Field Gradient Sensors (Gradiometer), igital Magnetic Field Sensors, igital Signal Isolators and Isolated Bus Transceivers. NVE is a leader in GM research and in 1994 introduced the world's first products using GM material, a line of GM magnetic field sensors that can be used for position, magnetic media, wheel speed and current sensing. NVE is located in Eden Prairie, Minnesota, a suburb of Minneapolis. Please visit our Web site at or call for information on products, sales or distribution. NVE Corporation Valley View oad Eden Prairie, MN USA Telephone: (952) Fax: (952) Internet: 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. The use of NVE Corporation s products in such applications is understood to be entirely at the customer's own risk. Specifications shown are subject to change without notice. ISB-S-001-IL485-

Isolated RS485 Interface With Handshake. Features 2500 V RMS. Applications. Description

Isolated RS485 Interface With Handshake. Features 2500 V RMS. Applications. Description NVE COPOTION IL485WISOLOOP Isolated S485 Interface With Handshake Functional iagram E GLVNIC ISOLTION ISO OUT 1 Features 2500 V MS Isolation (1 min) 25 ns Maximum Propagation elay 35 Maud ata ate 1 ns