Datasheet LTM2881 (Analog Devices)

LTM2881 Complete Isolated RS485/RS422 µModule Transceiver + Power
FeaTures DescripTion
n
RS485/RS422 Transceiver: 2500VRMS for 1 Minute
The LTM®2881 is a complete galvanically isolated full-du- n
UL-CSA Recognized File #E151738
plex RS485/RS422 µModule® (micromodule) transceiver. n
CSA Component Acceptance Notice 5A
No external components are required. A single supply n
Isolated DC Power: 5V at Up to 200mA
powers both sides of the interface through an integrated, n
No External Components Required
isolated, low noise, efficient 5V output DC/DC converter. n
20Mbps or Low EMI 250kbps Data Rate
Coupled inductors and an isolation power transformer n
High ESD: ±15kV HBM on Transceiver Interface
provide 2500VRMS of isolation between the line transceiver n
High Common Mode Transient Immunity: 30kV/μs
and the logic interface. This device is ideal for systems n
Integrated Selectable 120Ω Termination
where the ground loop is broken allowing for large com- n 3.3V (LTM2881-3) or 5.0V (LTM2881-5) Operation mon mode voltage variation. Uninterrupted communica- n 1.62V to 5.5V Logic Supply Pin for Flexible Digital Interface tion is guaranteed for common mode transients greater n Maximum Continuous Working Voltage: 560VPEAK than 30kV/μs. n High Input Impedance Failsafe RS485 Receiver n Current Limited Drivers and Thermal Shutdown Maximum data rates are 20Mbps or 250kbps in slew n Compatible with TIA/EIA-485-A and PROFIBUS limited mode. Transmit data, DI and receive data, RO, are n High Impedance Output During Internal Fault Condition implemented with event driven low jitter processing. The n Low Current Shutdown Mode (< 10µA) receiver has a one-eighth unit load supporting up to 256 n General Purpose CMOS Isolated Channel nodes per bus. A logic supply pin allows easy interfacing n 15mm × 11.25mm BGA and LGA Packages with different logic levels from 1.62V to 5.5V, independent of the main supply.
applicaTions
Enhanced ESD protection allows this part to withstand up n Isolated RS485/RS422 Interface to ±15kV (human body model) on the transceiver interface n Industrial Networks pins to isolated supplies and ±10kV through the isolation n Breaking RS485 Ground Loops barrier to logic supplies without latch-up or damage. n L Isolated PROFIBUS-DP Networks , LT, LTC, LTM, Linear Technology, the Linear logo and µModule are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.
Typical applicaTion Isolated Half-Duplex RS485 μModule Transceiver LTM2881 Operating Through 35kV/μs CM Transients
3.3V (LTM2881-3) 5V (LTM2881-5) MULTIPLE SWEEPS OF COMMON MODE TRANSIENTS VCC LTM2881 V AVAILABLE CURRENT: CC2 5V 500V/DIV PWR 150mA (LTM2881-5) VL A 100mA (LTM2881-3) RO B DI RE TWISTED-PAIR 1V/DIV RO TE CABLE DE TION BARRIER Y 1V/DIV DI ISOLA Z 2881 TA01a 50ns/DIV GND GND2 2881 TA01 2881fi For more information www.linear.com/LTM2881 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Switching Characteristics Isolation Characteristics Typical Performance Characteristics Pin Functions Block Diagram Test Circuits Functional Table Applications Information Typical Applications Package Description Revision History Typical Application Related Parts