Transceivers give industrial interface lines protection to 60V

February 11, 2016 // By Graham Prophet
This 3.3V/5V 20 Mbps RS-485 transceiver family provides ±60V fault protection for improved system reliability; Exar’s latest RS-485/RS-422 (TIA-485/TIA-422) transceivers are able to withstand direct shorts and achieve overvoltage protection with no external components.

Designed for improved performance in noisy industrial environments and increased tolerance to system faults, these transceivers simplify design in building automation, HVAC networks, energy metering, process control and other industrial automation applications, the device family initially comprises four parts: XR33053, XR33152, XR33156 and XR33158.

The XR33156 is the most feature-rich ±60V tolerant device on the market with cable invert control to correct for reversed bus pins and a low voltage logic pin, eliminating the need for a level shifter in low voltage applications. Other inherent protection features include ±25V common mode voltage, hot swap glitch protection, overload protection and enhanced receiver fail-safe protection for open, shorted or terminated but idle data lines. The transceivers also protect against ESD events exceeding ±15kV.

The XR33053, XR33152, XR33156 and XR33158 operate over a 3V to 5.5V supply voltage range with standby current of 1 µA (max), 1 nA (typ). They support data rates up to 20 Mbps in either full- or half-duplex configurations and operate over the standard industrial temperature range of -40˚C to 85˚C. Pricing is from $1.49 (1000).

Exar; Evaluation boards and samples are available at