LTC2859_12 Datasheet, PDF (1/18 Pages) Linear Technology – 20Mbps RS485 Transceivers

LTC2859/LTC2861
Features
20Mbps RS485 Transceivers
with Integrated Switchable
Termination
Description
n _{Integrated, Logic-Selectable 120Ω Termination}
Resistor
n _{20Mbps Max Data Rate}
n _{No Damage or Latchup to ESD: ±15kV HBM}
n _{High Input Impedance Supports 256 Nodes}
(C-, I-Grades)
n _{Operation Up to 105°C (LTC2859H)}
n _{250kbps Low-EMI Mode}
n _{Guaranteed Failsafe Receiver Operation Over the}
Entire Common Mode Range
n _{Current Limited Drivers and Thermal Shutdown}
n _{Delayed Micropower Shutdown (5µA Max)}
n _{Power Up/Down Glitch-Free Driver Outputs}
n _{Low Operating Current (900µA Max in Receive Mode)}
n _{Meets All TIA/EIA-485-A Specifications}
n _{Available in 10-Pin 3mm × 3mm DFN, 12-Pin}
4mm × 3mm DFN and 16-Pin SSOP Packages
Applications
n _{Low Power RS485/RS422 Transceiver}
n _{Level Translator}
n _{Backplane Transceiver}
L, 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.
The LTC^®2859 and LTC2861 are low power, 20Mbps
RS485/422 transceivers operating on 5V supplies. The
receiver includes a logic-selectable 120Ω termination,
one-eighth unit load supporting up to 256 nodes per bus
(C-, I-grades), and a failsafe feature that guarantees a high
output state under conditions of floating or shorted inputs.
The driver features a logic-selectable low-EMI 250kbps
operating mode, and 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 a thermal shutdown.
Enhanced ESD protection allows the LTC2859 and LTC2861
to withstand ±15kV (human body model) on the transceiver
interface pins without latchup or damage.
Product Selection Guide
PART NUMBER
LTC2859
LTC2861
DUPLEX
Half
Full
PACKAGE
DFN-10
SSOP-16, DFN-12
Typical Application
RO
R
RE
TE
DE
DI
D
SLO
LTC2859
120Ω
LTC2859
120Ω
120Ω
LTC2859
R
RO
RE
TE
DE
D
DI
SLO
2859/61 TA01
R
D
LTC2859 at 20Mbps
DI
Y
Z
Y–Z
2V/DIV
20ns/DIV
285961 TA02
RO RE TE DE DI SLO
285961fc
1