Features

• 20Mbps or Low EMI 250kbps Maximum Data Rate
• No Damage or Latchup to ESD: ±15kV HBM
• High Input Impedance Supports 256 Nodes (C, I-Grade)
• Operation Up to 125°C (H-Grade)
• Guaranteed Failsafe Receiver Operation Over the Entire Common Mode Range
• Current Limited Drivers and Thermal Shutdown
• Delayed Micropower Shutdown: 5μA Maximum (C, I-Grade)
• Power Up/Down Glitch-Free Driver Outputs
• Low Operating Current: 900μA Maximum in Receive Mode
• Compatible with TIA/EIA-485-A Specifications
• Available in 8-Lead and 10-Lead 3mm × 3mm DFN and 8-Lead and 10-Lead MSOP Packages

Typical Application

Description

The LTC®2856-1, LTC2856-2, LTC2857-1, LTC2857-2, LTC2858-1 and LTC2858-2 are low power, RS485/RS422 transceivers operating on 5V supplies at maximum data rates of 20Mbps or 250kbps for low EMI. The receiver has a one-eighth unit load, supporting up to 256 nodes per bus (C, I-Grade), and a failsafe 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 thermal shutdown.

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