ISL8485E
ESD Protected to ±15kV, 5V, Low Power, High Speed or Slew Rate Limited, RS-485/RS-422 Transceivers

Key Features

• Pb-Free Available (RoHS Compliant)
• 125°C Temperature Option
• RS-485 I/O Pin ESD Protection ±15kV HBM
• Class 3 ESD Level on all Other Pins >7kV HBM
• Specified for 10% Tolerance Supplies
• High Data Rate Version (ISL8485E) up to 10Mbps
• Slew Rate Limited Version for Error Free Data Transmission (ISL8483E) up to 250kbps
• Single Unit Load Allows up to 32 Devices on the Bus
• 1nA Low Current Shutdown Mode (ISL8483E)
• Low Quiescent Current:
• 160µA (ISL8483E)
• 500µA (ISL8485E)
• -7V to +12V Common Mode Input Voltage Range
• Three State Rx and Tx Outputs
• 30ns Propagation Delays, 5ns Skew (ISL8485E)
• Operate from a Single +5V Supply (10% Tolerance)
• Current Limiting and Thermal Shutdown for driver Overload Protection

Description

These Intersil RS-485, RS-422 devices are ESD protected, BiCMOS 5V powered, single transceivers that meet both the RS-485 and RS-422 standards for balanced communication. Each driver output/receiver input is protected against ±15kV ESD strikes, without latch-up. Unlike competitive devices, this Intersil family is specified for 10% tolerance supplies (4.5V to 5.5V).

The ISL8483E utilizes slew rate limited drivers which reduce EMI, and minimize reflections from improperly terminated transmission lines, or un-terminated stubs in multidrop and multi-point applications.

Data rates up to 10Mbps are achievable by using the ISL8485E which features higher slew rates. Both devices present a "single unit load" to the RS-485 bus, which allows up to 32 transceivers on the network. Receiver (Rx) inputs feature a "fail-safe if open" design, which ensures a logic high Rx output, if Rx inputs are floating.

Driver (Tx) outputs are short circuit protected, even for voltages exceeding the power supply voltage. Additionally, on-chip thermal shutdown circuitry disables the Tx outputs to prevent damage if power dissipation becomes excessive.

These half duplex configurations multiplex the Rx inputs and Tx outputs to allow transceivers with Rx and Tx disable functions in 8 lead packages.

Applications

• Factory Automation
• Security Networks
• Building Environmental Control Systems
• Industrial/Process Control Networks
• Level Translators (e.g., RS-232 to RS-422)
• RS-232 "Extension Cords"