Overview
Description
The ISL3245xE are 3. 3V to 5V powered, fault protected, extended Common-Mode Range (CMR) differential transceivers for balanced communication. The RS-485 bus pins (driver outputs and receiver inputs) are protected against overvoltages up to ±60V, and against ±15kV ESD strikes. These transceivers operate in environments with common-mode voltages up to ±20V (exceeds the RS-485 requirement), making this RS-485 family one of the most robust on the market. The transmitters are RS-485 compliant with VCC ≥ 4. 5V and deliver a 1. 1V differential output voltage into the RS-485 specified 54Ω load even with VCC = 3V. 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 full fail-safe operation is maintained even when the Rx input polarity is switched (cable invert function on ISL32457E and ISL32459E). The ISL32457E and ISL32459E include a cable invert function that reverses the polarity of the Rx and Tx bus pins in case the cable is misconnected during installation.
Features
- Fault protected RS-485 bus pins: up to ±60V
- Extended common-mode range: ±20V larger than required for RS-485
- ±15kV HBM ESD protection on RS-485 bus pins
- Wide supply range: 3V to 5.5V
- Cable invert pin (ISL32457E and ISL32459E only) corrects for reversed cable connections while maintaining Rx full fail-safe functionality
- 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
- Choice of RS-485 data rates: up to 20Mbps
- Low quiescent supply current: 2.1mA
Comparison
Applications
- Utility Meters/Automated Meter Reading Systems
- Air Conditioning Systems
- 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.