These Renesas RS-485/RS-422 devices are “fractional” Unit Load (UL), BiCMOS, 5V powered, single transceivers that meet both the RS-485 and RS-422 standards for balanced communication. Unlike competitive devices, this family is specified for 10% tolerance supplies (4. 5V to 5. 5V). The ISL81483 and ISL81487 present a 1/8 unit load to the RS-485 bus, which allows up to 256 transceivers on the network for large node count systems (for example, process automation, remote meter reading systems). In a remote utility meter reading system, individual (apartments for example) utility meter readings are routed to a concentrator through an RS-485 network, so the high allowed node count minimizes the number of repeaters required to network all the meters. Data for all meters is then read out from the concentrator using a single access port, or a wireless link. The slew rate limited driver on the ISL81483 reduces EMI, and minimizes reflections from improperly terminated transmission lines, or unterminated stubs in multidrop and multipoint applications. Data rates up to 250kbps are achievable with these devices. Data rates up to 5Mbps are achievable by using the ISL81487, 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. These half duplex devices multiplex the Rx inputs and Tx outputs to allow transceivers with Rx and Tx disable functions in 8 Ld packages.

Features

  • Fractional unit load allows up to 256 devices on the bus
  • Specified for 10% tolerance supplies
  • Class 3 ESD protection (HBM) on all pins: >7kV
  • High data rate version (ISL81487): up to 5Mbps
  • Slew rate limited version for error free data transmission (ISL81483): up to 250kbps
  • Low current shutdown mode (except ISL81487): 0.5µA
  • Low quiescent supply current: ISL81483: 145µA (Max., ISL81487: 420µA (Max.)
  • -7V to +12V common-mode input voltage range
  • Three state Rx and Tx outputs
  • 30ns propagation delays, 5ns skew (ISL81487)
  • Half duplex pinouts
  • Operate from a single +5V supply (10% tolerance)
  • Current limiting and thermal shutdown for driver overload protection
  • Drop-in replacements for: MAX1483 (ISL81483); MAX1487, LMS1487 (ISL81487)
  • Pb-free plus anneal available (RoHS compliant)

Applications

  • High Node Count Networks
  • Automated Utility Meter Reading Systems
  • Factory Automation
  • Security Networks
  • Building Environmental Control Systems
  • Industrial/Process Control Networks

tuneProduct Options

Part Number Part Status Pkg. Type Carrier Type MOQ Buy Sample
Active SOICN Tube 980
Availability
Active SOICN Reel 2500
Availability

descriptionDocumentation

Title language Type Format File Size Date
Datasheets & Errata
star ISL8487, ISL81483, ISL81487 Datasheet Datasheet PDF 836 KB
ISL81483, ISL81487 Datasheet Datasheet PDF 770 KB
Application Notes & White Papers
R15AN0002: RS-485 Transient Protection in Industrial DC-Supply Buses Application Note PDF 178 KB
How to Simplify Industrial PC Interfaces 简体中文 White Paper PDF 920 KB
AN1991: Isolating RS-485 Interfaces with High-Speed Digital Optocouplers Application Note PDF 513 KB
AN1990: RS-485 Transceivers in J1708 Physical Layer Applications of Heavy Duty Vehicles Application Note PDF 826 KB
AN1987: RS-485 External Fail-Safe Biasing for Isolated Long Haul Buses Application Note PDF 443 KB
AN1986: External Fail-Safe Biasing of RS-485 Networks Application Note PDF 582 KB
AN1985: Transient Protection for the Standard RS-485 Transceiver: ISL3152E Application Note PDF 335 KB
AN1989: RS-422 vs RS-485: Similarities and Key Differences Application Note PDF 440 KB
AN1976: Important Transient Immunity Tests for RS-485 Networks Application Note PDF 338 KB
AN1977: Transient Voltage Suppressors: Operation and Features Application Note PDF 365 KB
AN1978: Surge Protection for Intersil's Standard RS-485 Transceivers Application Note PDF 369 KB
AN1979: Surge Protection simplified with Intersil's Overvoltage Protected (OVP) Transceivers Application Note PDF 500 KB
AN1980: Ground Potential Differences: Origin and Remedies Application Note PDF 375 KB
PCNs & PDNs
PCN20017 - Alternate bond wire material and assembly facility of the listed Renesas nSOIC packaged products Product Change Notice PDF 266 KB
PA16061 - Introduce New T-type End Plug for n-SOIC rail (packing tube) Product Advisory PDF 106 KB
PCN15046 - Wafer Fabrication Site Change for Listed Intersil Products - Global Foundry P6 Process transfer to Palm Bay - Phase II Product Change Notice PDF 398 KB
PCN12068 - SOIC w/ Copper Bond Wire @ ASECL as Alternate Assembly Site Product Change Notice PDF 108 KB
Other
Analog ICs Brochure 日本語 Brochure PDF 4.20 MB
TB506: Functional Principles of RS-485 Drivers and Receivers Other PDF 156 KB
TB509: Detecting Bus Signals Correctly with Failsafe Biased RS-485 Receivers Other PDF 240 KB
TB511: The Unit Load Concept Other PDF 253 KB
TB505: Understanding the Difference between HBM and IEC 61000-4-2 ESD Immunity Other PDF 254 KB

file_downloadDownloads

Title language Type Format File Size Date
Models
isl81487 Model - Other IBS 47 KB