RS485 with 5000Vrms capacitive isolation — what it means for the bus
The MAX14942GWE+T is an isolated RS485 transceiver from Analog Devices that uses capacitive coupling to deliver 5000Vrms galvanic isolation between the bus side and the logic side. It runs at 20Mbps data rate, which is fast enough for most industrial multi-drop RS485 links including Modbus RTU at higher baud rates and Profibus DP. The part has three unidirectional channels — two inputs on side 1, one input on side 2 — so it handles the transmit/receive direction split without external direction control logic. No isolated power is built in; you supply a separate isolated DC-DC for the bus-side rail. The 16-SOIC wide-body package (7.50 mm width) gives the creepage distance needed to maintain the 5000Vrms rating across the isolation barrier. Operating temperature covers -40°C to 105°C, suited for industrial motor drives, PLC I/O modules, and outdoor telecom gear where ground potential differences are a given.
20Mbps and 68ns propagation — timing margin on the bus
A 20Mbps data rate with 68ns max propagation delay (both tpLH and tpHL) supports back-to-back byte streams without bit-slip on a properly terminated bus.
Active production — no LTB clock ticking
The MAX14942GWE+T carries an Active lifecycle status from Analog Devices. No last-time-buy notice or end-of-life announcement is available. The part is ROHS3 compliant.