ADM4854 5 V, ⅛ Load, Slew-Rate Limited, RS-485/RS-422 Transceiver (Full Duplex, 115 kbps)

The ADM4850 / ADM4851 / ADM4852 / ADM4853 / ADM4854 / ADM4855 / ADM4856 / ADM4857 are differential line transceivers suitable for high speed, half-duplex and full duplex data communication on multipoint bus transmission lines. They are designed for balanced data transmission and comply with EIA Standards RS-485 and RS-422. The ADM4850 / ADM4851 / ADM4852 / ADM4853 are half-duplex transceivers that share differential lines and have separate enable inputs for the driver and receiver. The full duplex ADM4854 / ADM4855 / ADM4856 / ADM4857 transceivers have dedicated differential line driver outputs and receiver inputs.

The devices have a 1/8-unit load receiver input impedance, which allows up to 256 transceivers on one bus. Because only one driver must be enabled at any time, the output of a disabled or powered down driver is three-stated to avoid overloading the bus.

The receiver inputs have a true fail-safe feature, which ensures a logic high output level when the inputs are open or shorted.

This guarantees that the receiver outputs are in a known state before communication begins and when communication ends. The driver outputs are slew rate limited to reduce EMI and data errors caused by reflections from improperly terminated buses. Excessive power dissipation caused by bus contention or by output shorting is prevented with a thermal shutdown circuit.

The devices are fully specified over the commercial and industrial temperature ranges and are available in 8-lead SOIC (ADM4850 through ADM4857), 8-lead LFCSP (ADM4850 / ADM4852 / ADM4853), and 8-lead MSOP (ADM4850 only) packages.

Applications

Features and Benefits
  • Electronics industries alliance (EIA) RS-485/RS-422 compliant
  • Data rate: 115 kbps
  • Half-duplex and full duplex options
  • Reduced slew rates for low electromagnetic interference (EMI)
  • True fail-safe receiver inputs
  • 5 µA (maximum) supply current in shutdown mode
  • Up to 256 transceivers on one bus
  • Outputs high-Z when disabled or powered off
  • −7 V to +12 V bus common-mode range
  • Thermal shutdown and short-circuit protection
  • Pin-compatible with the MAX308x
  • Specified over the −40°C to +85°C temperature range
  • Available in 8-lead SOIC, 8-lead LFCSP, and 8-lead MSOP
  • Qualified for automotive applications
  • Interface & Isolation
    Data Sheets
    Documentnote
    ADM4850-ADM4857: 5 V, Slew-Rate Limited, Half-Duplex and Full-Duplex RS-485/RS-422 Transceivers Data Sheet (Rev. F)PDF 336.21 K
    Application Notes
    Documentnote
    AN-1176: Component Footprints and Symbols in the Binary .Bxl File Format (Rev. 0)PDF 671 kB
    AN-960: RS-485/RS-422 Circuit Implementation Guide (Rev. 0)PDF 245 kB
    Order Information
    Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
    ADM4854AR Obsolete8 ld SOICOTH 9800N
    ADM4854AR-REEL7 Obsolete8 ld SOICREEL 100000N
    ADM4854ARZ Production8 ld SOICOTH 98-40 to 85C0.920.8Y
    Evaluation Boards
    Part NumberDescriptionPriceRoHS
    EVAL-RS485FD8EBZEvaluation Board30Y
    Reference Materials
    ADM4850-ADM4857: 5 V, Slew-Rate Limited, Half-Duplex and Full-Duplex RS-485/RS-422 Transceivers Data Sheet (Rev. F) adm4850
    AN-1176:二进制.Bxl文件格式的元件尺寸和符号 (Rev. 0) adn4670
    AN-1176: Component Footprints and Symbols in the Binary .Bxl File Format (Rev. 0) adn4670
    AN-960: RS-485/RS-422电路实施指南 (Rev. 0) adm2486
    AN-960: RS-485/RS-422 Circuit Implementation Guide (Rev. 0) adm2486
    Emerging Energy Applications Solutions Bulletin, Volume 10, Issue 4 ad7656
    Test & Instrumentation Solutions Bulletin, Volume 10, Issue 3 ad7780
    ADI RS-485/RS-422 Cross Reference Guide adm2486