Datasheet

12
LT1785/LT1785A
LT1791/LT1791A
 LINEAR TECHNOLOGY CORPORATION 1998
178591fa LT/TP 0501 2K REV A • PRINTED IN THE USA
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone]
●
FAX: [phone]
●
www.linear-tech.com
TYPICAL APPLICATIONS
U
RELATED PARTS
PART NUMBER DESCRIPTION COMMENTS
LTC485 Low Power RS485 Interface Transceiver I
CC
= 300µA (Typ)
LTC491 Differential Driver and Receiver Pair I
CC
= 300µA
LTC1483 Ultralow Power RS485 Low EMI Transceiver Controlled Driver Slew Rate
LTC1485 Differential Bus Transceiver 10Mbaud Operation
LTC1487 Ultralow Power RS485 with Low EMI, Shutdown and High Input Impedance Up to 256 Transceivers on the Bus
LTC1520 50Mbps Precision Quad Line Receiver Channel-to-Channel Skew 400ps (Typ)
LTC1535 Isolated RS485 Full-Duplex Transceiver 2500V
RMS
Isolation in Surface Mount Package
LTC1685 52Mbps RS485 Half-Duplex Transceiver Propagation Delay Skew 500ps (Typ)
LTC1687 52Mbps RS485 Full-Duplex Transceiver Propagation Delay Skew 500ps (Typ)
4
3
2
1
A
B
7
6
RO
RE
DE
DI
1785/91 F10
RX
TX
R
T
120Ω
R
T
120Ω
LT1785
4
3
2
1
A
B
7
6
RO
RE
DE
DI
RX
TX
LT1785
4
3
2
1
A
B
7
6
RO
RE
DE
DI
4
3
2
1
A
B
7
6
RO
RE
DE
DI
LT1785
LT1785
Figure 10. Half-Duplex RS485 Network Operation
4
3
2
1
A
B
7
8
V
CC
5
6
RO
RE
DE
DI
RX
TX
R
T
,120Ω
1785/91 F11
0.1µF
300V
47Ω
1.5KE36CA
47Ω
CARBON
COMPOSITE
5W
LT1785
RAYCHEM
POLYSWITCH
TR600-150
× 2
Figure 11. RS485 Network with 120V AC Line Fault Protection