Isolated RS-485 transceiver

I don't have an isolated supply available in my design, do you have any RS-485 transceivers available that contain isolated power?

  • 0
    •  Analog Employees 
    on Sep 26, 2011 7:27 PM over 9 years ago

    Yes, we do have RS-485 transceivers with integrated power isolation as well as signal isolation. The following parts all have isolated power using isoPower chip-scale micro-transformer technology:

    Part Number Isolation Rating Max. Data Rate
    ADM2582E 2.5 kV rms 16 Mbps
    ADM2587E 2.5 kV rms 500 kbps
    ADM2682E 5 kV rms with > 8mm Creepage and Clearance 16 Mbps
    ADM2687E 5 kV rms with > 8mm Creepage and Clearance 500 kbps

    These parts can be powered with Vcc of 3.3 V or 5 V on the logic side and have a 3.3V output on the bus side. All four parts are full duplex, with 15 kV ESD protection (HBM) on the bus pins, open/short/idle failsafe receivers and supporting 256 nodes on the bus.

    We also have RS-485 transceivers with an integrated transformer driver, to drive an external transformer providing the isolated supply for the bus side of the device.

    Part number Bus Side Power Max. Data Rate Duplex Nodes on Bus
    ADM2482E 2.5 kV rms 16 Mbps Full 256
    ADM2487E 2.5 kV rms 500 kbps Full 256
    ADM2485 2.5 kV rms 16 Mbps Half 50

    The ADM2485 is a Profibus compliant RS-485 transceiver that requires a 5 V supply on Vdd2. The ADM2482E/87E require a 3.3 V supply on Vdd2. Evaluation boards are available for these parts and external components (transformer, regulator) are recommended in the datasheets, with the exact choice of transformer dependent on whether 3.3 V or 5V is used for the primary supply (Vdd1).