LTC2854/LTC2855
3.3V 20Mbps RS485/RS422
Transceivers with Integrated
Switchable Termination
FEATURES DESCRIPTION
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Integrated, Logic-Selectable 120 Termination Resistor The LTC 2854 and LTC2855 are low power, 20Mbps
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3.3V Supply Voltage RS485/RS422 transceivers operating on 3.3V supplies.
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20Mbps Maximum Data Rate The receiver includes a logic-selectable 120 termination,
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No Damage or Latchup Up to 25kV HBM one-eighth unit load supporting up to 256 nodes per bus
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High Input Impedance Supports 256 Nodes (C-, I-Grade) (C-, I-Grade), and a failsafe feature that guarantees a high
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Operation Up to 125C (H-Grade) output state under conditions of floating or shorted inputs.
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Guaranteed Failsafe Receiver Operation Over the
The driver maintains a high output impedance over the
Entire Common Mode Range
entire common mode range when disabled or when the
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Current Limited Drivers and Thermal Shutdown
supply is removed. Excessive power dissipation caused by
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Delayed Micropower Shutdown: 5A Maximum (C-, I-Grade)
bus contention or a fault is prevented by current limiting
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Power Up/Down Glitch-Free Driver Outputs
all outputs and by a thermal shutdown.
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Low Operating Current: 370A Typical in Receive Mode
n Enhanced ESD protection allows the LTC2854 to withstand
Compatible with TIA/EIA-485-A Specifications
n 25kV (human body model) and the LTC2855 to withstand
Available in 10-Pin 3mm 3mm DFN, 12-Pin
15kV on the transceiver interface pins without latchup
4mm3mm DFN and 16-Pin SSOP Packages
or damage.
APPLICATIONS
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Low Power RS485/RS422 Transceiver
PRODUCT SELECTION GUIDE
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Level Translator
PART NUMBER DUPLEX PACKAGE
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Backplane Transceiver
LTC2854 HALF DFN-10
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.
LTC2855 FULL SSOP-16, DFN-12
TYPICAL APPLICATION
LTC2854 at 20Mbps into 54
LTC2854 LTC2854
RO R R RO
DI
RE RE
TE
TE
120
DE 120 DE
A
DI D D DI
B
2V/DIV
A-B
LTC2854 285455 TA01
120
285455 TA01b
R 20ns/DIV
D
RORE TE DE DI
285455fc
1
For more information www.linear.com/LTC2854LTC2854/LTC2855
ABSOLUTE MAXIMUM RATINGS (Note 1)
Supply Voltage (V ) ................................... 0.3V to 7V Operating Temperature (Note 4)
CC
Logic Input Voltages (RE, DE, DI, TE) ............ 0.3V to 7V LTC2854C, LTC2855C .............................. 0C to 70C
Interface I/O: LTC2854I, LTC2855I ............................40C to 85C
A, B, Y, Z .......................................(V 15V) to +15V LTC2854H, LTC2855H ....................... 40C to 125C
CC
(A-B) or (B-A) with Terminator Enabled ..................6V Storage Temperature Range .................. 65C to 150C
Receiver Output Voltage (RO) ........0.3V to (V +0.3V) Lead Temperature (Soldering, 10 sec)
CC
GN Package ......................................................300C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
TOP VIEW
1 16
RO V
CC
RO 1 12 V
CC
2 15
RE A
RO 1 10 V
CC RE 2 11 A
DE 3 14 B
RE 2 9 B
DE 3 10 B
13
11 4
DI 13 Z
DE 3 8 A
DI 4 9 Z
5 12
DI 4 7 NC TE Y
TE 5 8 Y
TE 5 6 GND
GND 6 11
NC
GND 6 7 NC
NC 7 10 NC
DD PACKAGE
8 9
NC NC
10-LEAD (3mm 3mm) PLASTIC DFN
DE PACKAGE
12-LEAD (4mm 3mm) PLASTIC DFN
EXPOSED PAD (PIN 11) PCB GND CONNECTION
GN PACKAGE
T = 150C, = 43C/W EXPOSED PAD (PIN 13) PCB GND CONNECTION
JMAX JA
16-LEAD (NARROW 0.150) PLASTIC SSOP
= 2.96C/W T = 150C, = 44C/W
JC
JMAX JA
T = 150C, = 110C/W
JMAX JA
= 4.3C/W
JC
= 40C/W
JC
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC2854CDD#PBF LTC2854CDD#TRPBF LCQG 10-Lead (3mm 3mm) Plastic DFN 0C to 70C
LTC2854IDD#PBF LTC2854IDD#TRPBF LCQG 10-Lead (3mm 3mm) Plastic DFN 40C to 85C
LTC2854HDD#PBF LTC2854HDD#TRPBF LCQG 10-Lead (3mm 3mm) Plastic DFN 40C to 125C
LTC2855CDE#PBF LTC2855CDE#TRPBF 2855 12-Lead (4mm 3mm) Plastic DFN 0C to 70C
LTC2855IDE#PBF LTC2855IDE#TRPBF 2855 12-Lead (4mm 3mm) Plastic DFN 40C to 85C
LTC2855HDE#PBF LTC2855HDE#TRPBF 2855 12-Lead (4mm 3mm) Plastic DFN 40C to 125C
LTC2855CGN#PBF LTC2855CGN#TRPBF 2855 16-Lead (Narrow 0.150) Plastic SSOP 0C to 70C
LTC2855IGN#PBF LTC2855IGN#TRPBF 2855I 16-Lead (Narrow 0.150) Plastic SSOP 40C to 85C
LTC2855HGN#PBF LTC2855HGN#TRPBF 2855H 16-Lead (Narrow 0.150) Plastic SSOP 40C to 125C
LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC2854CDD LTC2854CDD#TR LCQG 10-Lead (3mm 3mm) Plastic DFN 0C to 70C
LTC2854IDD LTC2854IDD#TR LCQG 10-Lead (3mm 3mm) Plastic DFN 40C to 85C
LTC2854HDD LTC2854HDD#TR LCQG 10-Lead (3mm 3mm) Plastic DFN 40C to 125C
LTC2855CDE LTC2855CDE#TR 2855 12-Lead (4mm 3mm) Plastic DFN 0C to 70C
LTC2855IDE LTC2855IDE#TR 2855 12-Lead (4mm 3mm) Plastic DFN 40C to 85C
LTC2855HDE LTC2855HDE#TR 2855 12-Lead (4mm 3mm) Plastic DFN 40C to 125C
LTC2855CGN LTC2855CGN#TR 2855 16-Lead (Narrow 0.150) Plastic SSOP 0C to 70C
LTC2855IGN LTC2855IGN#TR 2855I 16-Lead (Narrow 0.150) Plastic SSOP 40C to 85C
LTC2855HGN LTC2855HGN#TR 2855H 16-Lead (Narrow 0.150) Plastic SSOP 40C to 125C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: