The ISL32704E is a galvanically isolated, differential bus transceiver designed for bidirectional data transmission and meeting the RS-485 and RS-422 standards for balanced communication. Each of the bus terminals, A and B, is protected against ±15kV ESD strikes without latch-up. The device uses giant magnetoresistance (GMR) as isolation technology. A unique ceramic/polymer composite barrier provides excellent isolation and virtually unlimited barrier life. The part is available in a 16 Ld QSOP package offering unprecedented miniaturization, and in a 16 Ld wide-body SOIC package providing true 8mm creepage distance. The ISL32704E delivers a minimum differential output voltage of 1. 5V into a 54Ω differential load for excellent data integrity over long cable lengths. The device is compatible with 3V and 5V input 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.


  • 4Mbps data rate
  • 2.5kVRMS isolation per UL 1577
  • 600VRMS working voltage per VDE 0884
  • 3V to 5V power supplies
  • Single unit load receiver input
  • Driver drives up to 150 unit loads
  • 50kV/μs (typical), 30kV/μs (minimum) common-mode transient immunity
  • 44000 years barrier life
  • 15kV ESD bus-pin protection
  • Thermal shutdown protection
  • -40 °C to +85 °C temperature range
  • Meets or exceeds ANSI RS-485
  • 16 Ld QSOP and 0.3" true 8mm 16 Ld SOIC packages
  • UL 1577 recognized
  • VDE V0884-10 certified


  • Factory automation
  • Security networks
  • Building environmental control systems
  • Industrial/Process control networks
  • Level translators (i.e., RS-232 to RS-485)


Title language Type Format File Size Date
ISL32704E Datasheet Datasheet PDF 833 KB
R15AN0002: RS-485 Transient Protection in Industrial DC-Supply Buses Rev.1.00 Application Note PDF 178 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
AN1988: Isolated RS-485 Repeaters, the Backbone of Industrial Long Haul Networks Application Note PDF 769 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
AN1971: GMR In Isolation Application Note PDF 218 KB
AN1972: Giant-Magneto-Resistance as Digital Isolation Technology Application Note PDF 296 KB
AN1973: GMR Isolators in IEC61010-1 Edition 3 Systems Application Note PDF 213 KB
RS-485 Isolator Raises the Bar for Bus Node Designs White Paper PDF 437 KB
PA18003 - Datasheet specification change for Listed Intersil ISL32704E* Products Product Advisory PDF 180 KB
Analog ICs Brochure 日本語 Brochure PDF 4.20 MB
TB506: Functional Principles of RS-485 Drivers and Receivers Other PDF 156 KB
TB511: The Unit Load Concept Other PDF 253 KB
PIN19028 - Q3 Cy 19 Price Increase Notice Price Increase Notice PDF 208 KB
TB509: Detecting Bus Signals Correctly with Failsafe Biased RS-485 Receivers Technical Brief PDF 300 KB


memoryBoards & Kits

Part Number Title Type Company
ISL32704EVAL1Z Low-Cost Isolated RS-485 Transceiver Evaluation Board Evaluation Renesas

printNews & Additional Resources