LTC2803 LINER [Linear Technology], LTC2803 Datasheet - Page 22

• Manufacturer Part Number: LTC2803
• Description: Multiprotocol Transceiver
• Manufacturer: LINER [Linear Technology]

state. External components necessary for operation are not shown.
LTC2872
Typical applicaTions
22
V
L
DY1
DZ1
RA1
RB1
DY2
DZ2
RA2
RB2
PORT 1: RS232
PORT 2: RS232
Figure 21. Loopback in
RS232 and RS485 Modes
DY1
DZ1
RA1
RB1
DY2
RA2
LB
485/232_2
LTC2872
485/232_1
485/232_2
LTC2872
LB
Y1
A1
B1
Y2
A2
B2
Z1
Z2
485/232_1
RXEN1
RXEN2
GND
2872 F21
H/F
Y1
A1
B1
Y2
A2
B2
Z1
Z2
V
L
Figure 20. LTC2872 in Various Basic Port Configurations
DY1
DZ1
RA1
RB1
DY2
RA2
485/232_2
PORT 1: RS232
PORT 2: RS485
V
LTC2872
CC
= 3V to 5.5V, V
Figure 22. Half-Duplex RS485
Mode with Driver and Receiver Line
Termination on Each Port
V
485/232_1
L
GND
DY1
RA1
DY2
RA2
H/F
TE485_1
TE485_2
485/232_1
485/232_2
DZ1
DZ2
H/F
LB
Y1
Z1
A1
B1
Y2
Z2
A2
B2
LTC2872
L
= 1.7V to V
V
120Ω
120Ω
L
120Ω
120Ω
GND
2872 F22
DY1
RB1
DY2
DZ2
RA2
RB2
485/232_1
LB
Y1
Z1
A1
B1
Y2
Z2
A2
B2
PORT 1: RS485
PORT 2: RS232
CC
. Logic input pins not shown are tied to a valid logic
LTC2872
485/232_2
GND
H/F
LB
Y1
Z1
A1
B1
Y2
Z2
A2
B2
Figure 23. Full-Duplex RS485 Mode
with Driver and Receiver Line
Termination on Port 1, and Receiver-
Only Termination on Port 2
V
L
DY1
RA1
DY2
RA2
TE485_1
TE485_2
DZ1
485/232_1
485/232_2
V
L
DY1
RA1
DY2
RA2
485/232_1
485/232_2
PORT 1: RS485
PORT 2: RS485
LTC2872
LTC2872
120Ω
120Ω
120Ω
GND
2872 F23
DZ2
H/F
LB
Y1
Z1
A1
B1
Y2
Z2
A2
B2
GND
H/F
LB
Y1
Z1
A1
B1
Y2
Z2
A2
B2
2872 F20
2872f