LTC2856-1/LTC2856-2
LTC2857-1/LTC2857-2
LTC2858-1/LTC2858-2
1
285678fe
TYPICAL APPLICATION
FEATURES
APPLICATIONS
DESCRIPTION
20Mbps and Slew Rate
Limited 15kV RS485/RS422
Transceivers
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 fl oating 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.
■
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 Specifi cations
■
Available in 8-Lead and 10-Lead 3mm × 3mm DFN
and 8-Lead and 10-Lead MSOP Packages
■
Low Power RS485/RS422 Transceiver
■
Level Translator
■
Backplane Transceiver
V
CC1
GND1
R
RO1
RE1
DE1
DI1
D
R
T
LTC2856-1
LTC2856-1
R
T
285678 TA01a
V
CC2
GND2
R
RO2
RE2
DE2
DI2
D
PART
NUMBER
MAX DATA
RATE (Mbps) DUPLEX PACKAGE
LTC2856-1 20 Half MSOP-8, DFN-8
LTC2856-2 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 0.25 Full MSOP-10, DFN-10
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
DI
Y
Z
Y-Z
20ns/DIV
2856 TA01b
2V/DIV
LTC2858-1 at 20Mbps