Overview

Description

The ISL31470E, ISL31472E, ISL31475E, and ISL31478E are fault protected, extended common-mode range differential transceivers that exceed the RS-485 and RS-422 standards for balanced communication. The RS-485 bus pins (driver outputs and receiver inputs) are protected against overvoltages up to ±60V. Additionally, these transceivers operate in environments with common-mode voltages up to ±15V (exceeds the RS-485 requirement), making this RS-485 family one of the more 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 topologies. The receiver (Rx) inputs feature a Full Fail-Safe design that ensures a logic high Rx output if the Rx inputs are floating, shorted, or on a terminated but undriven (idle) bus. The Rx outputs feature high drive levels - typically 15mA at VOL = 1V (to ease the design of opto-coupled isolated interfaces). Half duplex (Rx inputs and Tx outputs multiplexed together) and full duplex pinouts are available. For an RS-485 family with a ±25V extended common-mode range, see the ISL31490E datasheet.

Features

  • Fault protected RS-485 bus pins: up to ±60V
  • Extended common-mode range: ±15V larger than 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)

Comparison

Applications

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

Documentation

Design & Development

Models

Support