The ISL32490E, ISL32492E, ISL32493E, ISL32495E, ISL32496E, and ISL32498E 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 (CMR) 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 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 RS-485 transceivers with cable invert (polarity reversal) pins, see the ISL32483E datasheet.
Feature
- Fault protected RS-485 bus pins: up to ±60V
- Extended CMR: ±25V (more than twice the range required for RS-485)
- ±16.5kV HBM ESD protection on RS-485 bus pins
- 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
