Overview
Description
The ISL32483E and ISL32485E (ISL3248xE) 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 fault protected up to ±60V and are protected against ±16. 5kV ESD strikes without latch‑up. 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 fault-protected RS-485 family one of the most robust on the market. The transmitters (Tx) 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. 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 ISL32483E and ISL32485E include cable invert functions that reverse the polarity of the Rx and/or Tx bus pins if the cable is misconnected. Unlike competing devices, the Rx full fail-safe operation is maintained even when the Rx input polarity is switched. For fault protected RS‑485 transceivers without the cable invert function, see the ISL32470E and ISL32490E datasheets.
Features
- Fault protected RS-485 bus pins: up to ±60V
- Extended common-mode range: ±25V more than twice the range required for RS-485
- ±16.5kV HBM ESD protection on RS-485 bus pins
- Cable invert pins corrects for reversed cable connections while maintaining Rx full fail-safe functionality
- Full fail-safe (open, short, terminated) RS-485 receivers
- 1/4 Unit Load (UL) for up to 128 devices on the bus
- High Rx IOL for opto-couplers in isolated designs
- Hot plug circuitry: Tx and Rx outputs remain three‑state during power-up/power-down
- Slew rate limited RS-485 data rate: 1Mbps
- Low quiescent supply current: 2.3mA
- Ultra low shutdown supply current: 10µA
Comparison
Applications
- Utility Meters/Automated Meter Reading Systems
- High Node Count RS-485 Systems
- PROFIBUS® and RS-485 Based Field Bus Networks, and Factory Automation
- Security Camera Networks
- Building Lighting and Environmental Control Systems
- Industrial/Process Control Networks
Design & Development
Models
ECAD Models
Schematic symbols, PCB footprints, and 3D CAD models from SamacSys can be found by clicking on products in the Product Options table. If a symbol or model isn't available, it can be requested directly from the website.