LTC1334 - Single 5V RS232/RS485 Multiprotocol Transceiver


  • Four RS232 Transceivers or Two RS485 Transceivers on One Chip
  • Operates from a Single 5V Supply
  • Withstands Repeated ±10kV ESD Pulses
  • Uses Small Charge Pump Capacitors: 0.1µF
  • Low Supply Current: 8mA Typical
  • 10µA Supply Current in Shutdown
  • Self-Testing Capability in Loopback Mode
  • Power-Up/Down Glitch-Free Outputs
  • Driver Maintains High Impedance in Three-State, Shutdown or with Power Off
  • Thermal Shutdown Protection
  • Receiver Inputs Can Withstand ±25V

Typical Application

LTC1334 Typical Application


The LTC®1334 is a low power CMOS bidirectional transceiver featuring two reconfigurable interface ports. It can be configured as two RS485 differential ports, as two dual RS232 single-ended ports or as one RS485 differential port and one dual RS232 single-ended port. An onboard charge pump requires four 0.1µF capacitors to generate boosted positive and negative supplies, allowing the RS232 drivers to meet the RS232 ±5V output swing requirement with only a single 5V supply. A shutdown mode reduces the ICC supply current to 10µA. The RS232 transceivers are in full compliance with RS232 specifications. The RS485 transceivers are in full compliance with RS485 and RS422 specifications. All interface drivers feature short-circuit and thermal shutdown protection. An enable pin allows RS485 driver outputs to be forced into high impedance, which is maintained even when the outputs are forced beyond supply rails or power is off. Both driver outputs and receiver inputs feature ±10kV ESD protection. A loopback mode allows the driver outputs to be connected back to the receiver inputs for diagnostic self-test.


CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

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

Part Number Package Code Temp Package
LTC1334CG#PBF SSOP-28 G C 05-08-1640 (G28) Yes
LTC1334CG#TRPBF SSOP-28 G C 05-08-1640 (G28) Yes
LTC1334CNW#PBF NW-28 NW C 05-08-1520 Yes
LTC1334CSW#PBF SW-28 SW C 05-08-1620 (SW28) Yes
LTC1334CSW#TRPBF SW-28 SW C 05-08-1620 (SW28) Yes
LTC1334IG#PBF SSOP-28 G I 05-08-1640 (G28) Yes
LTC1334IG#TRPBF SSOP-28 G I 05-08-1640 (G28) Yes
LTC1334INW#PBF NW-28 NW I 05-08-1520 Yes
LTC1334ISW#PBF SW-28 SW I 05-08-1620 (SW28) Yes
LTC1334ISW#TRPBF SW-28 SW I 05-08-1620 (SW28) Yes

LTC1334 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

Package Variations and Pricing

Part Number Package Temp Price
LTC1334CG#PBF SSOP-28 C $8.25 $6.90 Yes
LTC1334CG#TRPBF SSOP-28 C $7.00 Yes
LTC1334CNW#PBF NW-28 C $8.15 $6.50 Yes
LTC1334CSW#PBF SW-28 C $8.15 $6.50 Yes
LTC1334CSW#TRPBF SW-28 C $6.60 Yes
LTC1334IG#PBF SSOP-28 I $9.40 $7.90 Yes
LTC1334IG#TRPBF SSOP-28 I $8.00 Yes
LTC1334INW#PBF NW-28 I $9.50 $7.60 Yes
LTC1334ISW#PBF SW-28 I $9.50 $7.60 Yes
LTC1334ISW#TRPBF SW-28 I $7.70 Yes
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

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


  • Low Power RS485/RS422/RS232/EIA562 Interface
  • Software-Selectable Multiprotocol Interface Port
  • Cable Repeaters
  • Level Translators

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