LTC2856-1/LTC2856-2
LTC2857-1/LTC2857-2
LTC2858-1/LTC2858-2
20Mbps and Slew Rate
Limited 15kV RS485/RS422
Transceivers
Description
Features
20Mbps or Low EMI 250kbps Maximum Data Rate
n No Damage or Latchup to ESD: ±15kV HBM
n High Input Impedance Supports 256 Nodes
(C, I-Grade)
n Operation Up to 125°C (H-Grade)
n Guaranteed Failsafe Receiver Operation Over the
Entire Common Mode Range
n Current Limited Drivers and Thermal Shutdown
n Delayed Micropower Shutdown: 5µA Maximum
(C, I-Grade)
n Power Up/Down Glitch-Free Driver Outputs
n Low Operating Current: 900µA Maximum in Receive
Mode
n Compatible with TIA/EIA-485-A Specifications
n Available in 8-Lead and 10-Lead 3mm × 3mm DFN
and 8-Lead and 10-Lead MSOP Packages
n
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.
PART
NUMBER
PACKAGE
20
Half
MSOP-8, DFN-8
0.25
Half
MSOP-8, DFN-8
LTC2857-1
20
Full
MSOP-8, DFN-8
LTC2857-2
0.25
Full
MSOP-8, DFN-8
LTC2858-1
20
Full
MSOP-10, DFN-10
LTC2858-2
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
DUPLEX
LTC2856-2
Low Power RS485/RS422 Transceiver
n Level Translator
n Backplane Transceiver
n
MAX DATA
RATE (Mbps)
LTC2856-1
Applications
0.25
Full
MSOP-10, DFN-10
Typical Application
LTC2858-1 at 20Mbps
LTC2856-1
RO1
RE1
R
VCC1
DE1
D
Y
GND1
LTC2856-1
RO2
RE2
R
Z
2V/DIV
DI1
DI
RT
VCC2
RT
Y-Z
DE2
DI2
D
GND2
20ns/DIV
285678 TA01a
2856 TA01b
285678ff
For more information www.linear.com/LTC2856-1
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