3.3V 20Mbps RS485/RS422 Transceiver with Integrated Switchable Termination

The LTC2854 and LTC2855 are low power, 20Mbps RS485/RS422 transceivers operating on 3.3V supplies. The receiver includes a logic-selectable 120Ω termination, one-eighth unit load supporting up to 256 nodes per bus (C-, I-Grade), and a fail-safe feature that guarantees a high output state under conditions of floating or shorted inputs.

The driver maintains a high output impedance over the entire common mode range when disabled or when the supply is removed. Excessive power dissipation caused by bus contention or a fault is prevented by current limiting all outputs and by a thermal shutdown.

Enhanced ESD protection allows the LTC2854 to withstand ±25kV (human body model) and the LTC2855 to withstand ±15kV on the transceiver interface pins without latchup or damage.

Part Number

Duplex

Package

LTC2854

Half

DFN-10

LTC2855

Full

SSOP-16, DFN-12

Applications

* Low Power RS485/RS422 Transceiver

* Level Translator

* Backplane Transceiver

* Integrated, Logic-Selectable 120Ω Termination Resistor

* 3.3V Supply Voltage

* 20Mbps Maximum Data Rate

* No Damage or Latchup Up to ±25kV HBM

* High Input Impedance Supports 256 Nodes (C-, I‑Grade)

* Operation Up to 125°C (H-Grade)

* Guaranteed Fail-safe Receiver Operation Over the Entire Common Mode Range