2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex RS-485/RS-422 Transceivers with ±35kV ESD Protection and Integrated Transformer Driver

Industry's Most Robust Isolated RS-485

Please check latest availability status for a specific part variant.


The MAX14853/MAX14855 isolated RS-485/RS-422 transceivers provide 2750VRMS (60s) of galvanic isolation between the cable-side (RS-485/RS-422 driver/ receiver-side) and the UART-side of the device. Isolation improves communication by breaking ground loops and reduces noise when there are large differences in ground potential between ports. These devices allow for robust communication up to 500kbps (MAX14853) or 25Mbps (MAX14855).

The MAX14853/MAX14855 include an integrated 450kHz transformer driver for power transfer to the cable-side of the transceiver using an external transformer. An integrated LDO provides a simple and space-efficient architecture for providing power to the cable-side of the IC.

The MAX14853/MAX14855 include one drive channel and one receive channel. The receiver is ¼-unit load, allowing up to 128 transceivers on a common bus.

Integrated true fail-safe circuitry ensures a logic-high on the receiver output when inputs are shorted or open. Undervoltage lockout disables the driver when cable-side or UART-side power supplies are below functional levels.

The driver outputs and receiver inputs are protected from ±35kV electrostatic discharge (ESD) to GNDB on the cable-side, as specified by the Human Body Model (HBM).

The MAX14853/MAX14855 are available in a wide body 16-pin SOIC package and operate over the -40°C to +105°C temperature range.

MAX14853, MAX14855: Functional Diagram MAX14853, MAX14855: Functional Diagram Enlarge+

Key Features

  • Higher Integration Simplifies Designs
    • Integrated LDO for Powering Cable-Side
    • Integrated Transformer Driver for Power Transfer to Cable-Side
  • High-Performance Transceiver Enables Flexible Designs
    • Compliant with RS-485 EIA/TIA-485 Standard
    • 500kbps (MAX14853)/25Mbps (MAX14855) Maximum Data Rate
    • Up to 128 Devices on the Bus
    • Slew-Rate Limited Outputs (MAX14853)
    • Integrated Receiver Deglitch Filter Increases Noise Immunity (MAX14853)
  • Integrated Protection Ensures for Robust Communication
    • ±35kV ESD (HBM) on Driver Outputs/Receiver Inputs
    • 2.75kVRMS Withstand Isolation Voltage for 60s (VISO)
    • 630VPEAK Maximum Repetitive Peak Isolation Voltage (VIORM)
    • 445VRMS Maximum Working Isolation Voltage (VIOWM)
    • > 30 Years Lifetime at Rated Working Voltage
    • Withstands ±10kV Surge per IEC 61000-4-5
    • Thermal Shutdown


  • HVAC
  • Industrial Automation Equipment
  • Power Meters
  • Programmable Logic Controllers

See parametric specs for RS-485/RS-422 Line Driver/Receivers (208)

Part NumberTx/RxDuplexVSUPPLY
Galvanic Isolation
Data Rate
ESD Protect.
Tx ENRx ENRx/Tx on BusOper. Temp.
typminSee Notes
MAX14853 1Tx + 1RxFull3.0 to 5.527504.750035YesYes128-40 to +105
$3.82 @1k
MAX14855 25000
$4.20 @1k

Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

MAX148X2EVKIT: Evaluation Kit for the MAX14853/MAX14855/MAX14857 and MAX14859

Tools & Models

  • MAX14855 IBIS Model
  • Product Reliability Reports: MAX14855.pdf 
    Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C   Material Composition  

    Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

    Quality Management System >
    Environmental Management System >


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