ISL31491E: ±60V Fault Protected, 5V, RS-485/RS-422 Transceivers with ±25V Common Mode Range

The ISL31490E, ISL31491E, ISL31492E, ISL31493E, ISL31495E, ISL31496E, ISL31498E are fault protected, 5V powered, differential transceivers that exceed the RS-485 and RS-422 standards for balanced communication. The RS-485 transceiver pins (driver outputs and receiver inputs) are protected against faults up to ±60V. Additionally, the extended common mode range allows these transceivers to operate in environments with common mode voltages up to ±25V (>2x the RS-485 requirement), making this RS-485 family one of the most robust on the market.

Transmitters deliver an exceptional 2.5V (typical) differential output voltage into the RS-485 specified 54Ω load. This yields better noise immunity than standard RS-485 ICs, or allows up to six 120Ω terminations in star network topologies.

Receiver (Rx) inputs feature a “Full Fail-safe” design, which ensures a logic high Rx output if Rx inputs are floating, shorted, or on a terminated but undriven (idle) bus. Rx outputs have high drive levels - typically 15mA at VOL = 1V (for opto-coupled, isolated applications).

Half duplex (Rx inputs and Tx outputs multiplexed together) and full duplex pinouts are available. See Table 1 on page 3 for key features and configurations by device number. For fault protected or wide common mode range devices with cable invert (polarity reversal) please see the ISL32485E datasheet.

Key Features
  • Fault protected RS-485 bus pins: up to ±60V
  • Extended common mode range: ±25V More than twice the range required for RS-485
  • 1/4 unit load for up to 128 devices on the bus
  • High transient overvoltage tolerance: ±80V
  • Full fail-safe (open, short, terminated) RS-485 receivers
  • High Rx IOL for opto-couplers in isolated designs
  • Hot plug circuitry - Tx and Rx outputs remain three-state during power-up/power-down
  • Choice of RS-485 data rates: 250kbps to 15Mbps
  • Low quiescent supply current: 2.3mA
  • Ultra low shutdown supply current: 10μA
  • Pb-free (RoHS compliant)
Applications
  • Utility meters/automated meter reading systems
  • High node count systems
  • PROFIBUS™ and field bus networks, and factory automation
  • Security camera networks
  • Building lighting and environmental control systems
  • Industrial/process control networks
Typical Diagram
Application Notes
TitleTypeUpdatedSizeOther Languages
AN1979: Surge Protection simplified with Intersil’s Overvoltage Protected (OVP) TransceiversPDF24 Aug 2016250 KB
AN1978: Surge Protection for Intersil’s Standard RS-485 TransceiversPDF18 Aug 2016199 KB
AN1976: Important Transient Immunity Tests for RS-485 NetworksPDF10 Aug 2016156 KB
AN1977: Transient Voltage Suppressors: Operation and FeaturesPDF09 Aug 2016198 KB
AN1980: Ground Potential Differences: Origin and RemediesPDF29 Jul 2016198 KB
Datasheets
TitleTypeUpdatedSizeOther Languages
ISL31490E, ISL31491E, ISL31492E, ISL31493E, ISL31495E, ISL31496E, ISL31498E DatasheetPDF13 May 20151.12 MB
Tech Briefs
TitleTypeUpdatedSizeOther Languages
TB505: Understanding the Difference between HBM and IEC 61000-4-2 ESD ImmunityPDF29 Jul 2016121 KB
Order Information
Part NumberPackage TypeWeight(g)PinsMSL RatingPeak Temp (°C)RoHS Status
ISL31491EIBZ8 Ld SOIC0.07282260RoHS
ISL31491EIBZ-T8 Ld SOIC T+R0.07282260RoHS
ISL31491EIBZ-T7A8 Ld SOIC T+R0.07282260RoHS
ISL31490E, ISL31491E, ISL31492E, ISL31493E, ISL31495E, ISL31496E, ISL31498E Datasheet 13 May 2015
8 Ld SOIC T+R ISL84514
ISL31491E IBIS Model 06 Nov 2014
ISL31495E
AN1979: Surge Protection simplified with Intersil’s Overvoltage Protected (OVP) Transceivers 24 Aug 2016
AN1978: Surge Protection for Intersil’s Standard RS-485 Transceivers 18 Aug 2016
AN1976: Important Transient Immunity Tests for RS-485 Networks 10 Aug 2016
AN1977: Transient Voltage Suppressors: Operation and Features 09 Aug 2016
AN1980: Ground Potential Differences: Origin and Remedies 29 Jul 2016
TB505: Understanding the Difference between HBM and IEC 61000-4-2 ESD Immunity 29 Jul 2016