LTC2857-2_15 Datasheet, PDF (1/20 Pages) Linear Technology – 20Mbps and Slew Rate Limited 15kV RS485/RS422 Transceivers

Features
n _{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
Applications
n _{Low Power RS485/RS422 Transceiver}
n _{Level Translator}
n _{Backplane Transceiver}
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.
LTC2856-1/LTC2856-2
LTC2857-1/LTC2857-2
LTC2858-1/LTC2858-2
20Mbps and Slew Rate
Limited 15kV RS485/RS422
Transceivers
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.
PART
NUMBER
LTC2856-1
LTC2856-2
LTC2857-1
LTC2857-2
LTC2858-1
LTC2858-2
MAX DATA
RATE (Mbps)
20
0.25
20
0.25
20
0.25
DUPLEX
Half
Half
Full
Full
Full
Full
PACKAGE
MSOP-8, DFN-8
MSOP-8, DFN-8
MSOP-8, DFN-8
MSOP-8, DFN-8
MSOP-10, DFN-10
MSOP-10, DFN-10
Typical Application
LTC2856-1
RO1
R
RE1
V_CC1
DE1
DI1
D
GND1
LTC2856-1
RO2
R
RE2
V_CC2
DE2
DI2
D
GND2
285678 TA01a
LTC2858-1 at 20Mbps
DI
R_T
Y
Z
R_T
Y-Z
For more information www.linear.com/LTC2856-1
20ns/DIV
2856 TA01b
285678ff
1