What this isolator does on the bus
The ADM2487EBRWZ is a 3-channel, unidirectional, magnetic-coupled digital isolator from Analog Devices' iCoupler® family, purpose-built for RS422 and RS485 communication links. It provides 2500 Vrms galvanic isolation between the logic-side interface and the bus-side transceiver, with a maximum data rate of 500 kbps. Typical applications include industrial fieldbus nodes, programmable logic controllers (PLCs), motor-drive communication ports, and isolated RS485/RS422 networks in factory automation and building management systems.
The 500 kbps maximum data rate places this part in the mid-speed tier for isolated RS485 transceivers. At this rate, cable runs up to several hundred metres are practical with standard twisted-pair wiring, making it a fit for sensor networks, actuator control, and Modbus RTU links where throughput above 115.2 kbps is needed but full 16 Mbps (as on the ADM2482EBRWZ) is not. The 1.1 µs rise/fall time limits edge-rate emissions, which helps pass radiated-emission tests without ferrite beads on every node.
Isolation and transient immunity
Rated for 2500 Vrms isolation and a minimum common-mode transient immunity of 25 kV/µs, the ADM2487EBRWZ handles the voltage transients common in motor-drive and inverter-fed environments. The 25 kV/µs CMTI ensures that fast-switching power stages do not corrupt the data on the bus — a critical parameter when the isolator bridges a noisy high-voltage domain to a sensitive logic controller.
Supply and channel configuration
The three unidirectional channels are arranged as two inputs on side 1 and one input on side 2 — typical for a half-duplex RS485 node where the logic-side UART TX and RX plus a driver-enable signal cross the isolation barrier.
Package and footprint
Housed in a 16-pin SOIC with 7.50 mm body width (0.295″), the ADM2487EBRWZ uses the standard wide-body SOIC footprint common to many iCoupler isolators. The surface-mount package is suited for automated assembly and reflow processes. No isolated power is generated on-chip — the bus-side supply must be provided externally.
Lifecycle and sourcing
It is ROHS3 compliant.