LTC1318 - Single 5V RS232/RS422/AppleTalk DCE Transceiver


  • THIS PRODUCT IS OBSOLETE: Contact Linear Technology for Potential Replacement
  • Single Chip Provides DCE RS232 or RS422/AppleTalk DCE Port
  • Operates from a Single 5V Supply
  • Charge Pump Uses 0.1µF Capacitors
  • Output Common-Mode Voltage Range Exceeds Power Supply Rails for All Drivers
  • Driver Outputs Are High Impedance with Power Off
  • Pin Selectable RS232/RS422 Receiver
  • Thermal Shutdown Protection
  • Drivers Are Short-Circuit Protected

Typical Application

LTC1318 Typical Application
LTC1318 Typical Application


THIS PRODUCT IS OBSOLETE: Contact Linear Technology for Potential Replacement

The LTC1318 is a single 5V, RS232/RS422 transceiver for connection to the DCE, or peripheral side of an interface link. It includes an on-board charge pump to generate a ±8V supply which allows true RS232 output swings. The charge pump requires only four external 0.1µF capacitors. The LTC1318 includes two RS232 drivers, a differential RS422 driver, a dedicated RS232 receiver, and a pin selectable RS232/RS422 receiver which can receive either single-ended or differential signals. The LTC1318 features driver outputs which can be taken to common-mode voltages outside the power supply rails without damage. Additionally, the driver outputs assume a high impedance state when the power is shut off, preventing externally applied signals from feeding back into the power supplies. The RS232 devices will operate at speeds up to 100kbaud. The RS422 devices will operate up to 2Mbaud. The LTC1318 is available in a 24-lead SO Wide package.


For complete and up to date package information and drawings, please refer to our packaging page

LTC1318 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Click here to view our complete list of demo boards


  • Dual-Mode RS232/RS422 Peripherals
  • AppleTalk Peripherals
  • Single 5V Systems

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Design Tools

Linear Technology provides a variety of custom design simulation tools and device models to allow even novice designers to quickly and easily evaluate circuits using high performance switching regulators, amplifiers, data converters, filters and more. Please visit our Design Tools page to view and download:

  • LTspice - A powerful SPICE simulator, schematic capture and waveform viewer with enhancements and models for easing the simulation of switching regulators
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