ltc2871fe Linear Technology Corporation, ltc2871fe Datasheet - Page 26

• Manufacturer Part Number: ltc2871fe
• Description: Ltc2870/ltc2871 - Rs232/rs485 Multiprotocol Transceivers With Integrated Termination
• Manufacturer: Linear Technology Corporation

LTC2870/LTC2871
TYPICAL APPLICATIONS
V
26
D R 485
D R 232
FULL
CC
DUPLEX
RS485
= 3V to 5.5V, V
HALF
V
V
Figure 35. RS485 Duplex Switching
L
L
Figure 32. LTC2871 in RS485 and
RS232 Mode, Both Half-Duplex
DIN1
ROUT1
DIN2
H/F
DX485
RX485
DX232
RX232
DI
RO
ROUT2
485/232
TE485
DI
DY
H/F
RO
RB
L
= 1.7V to V
LTC2871
LTC2870/
LTC2871
GND
GND
CC
. Logic input pins not shown are tied to a valid logic state.
DOUT1
DOUT2
TE485
120Ω
120Ω
28701 F32
RIN1
RIN2
28701 F35
CH2
H/F
LB
LB
Y
Z
Y
Z
A
B
Figure 33. LTC2871 in RS485 and RS232
Mode, RS485 Half-Duplex, Loopback
V
1.7V TO V
L
CONTROL
SIGNALS
Figure 36. Microprocessor Interface
μP
DIN1
ROUT1
DIN2
DX232
DX485
H/F
LB
DI
RO
ROUT2
CC
3V TO 5.5V
LTC2871
GND
V
V
DY, DIN1
RA, ROUT1
DZ, DIN2
RB, ROUT2
CC
L
LTC2870/
LTC2871
DOUT1
DOUT2
RX232
RX485
TE485
28701 F33
GND
RIN1
RIN2
CH2
Y
Z
28701 F36
Y
A
Z
B
V
L
Figure 34. LTC2871 in RS485
and RS232 Mode, RS485
Half-Duplex, Terminated
DIN1
ROUT1
DIN2
DX232
DX485
H/F
TE485
DI
RO
ROUT2
DATA RATE
Figure 37. Driving Larger
RS232 Loads
100kbps
500kbps
LTC2870/
LTC2871
LTC2871
5nF
1nF
C
GND
L
RS232
28701 F37
120Ω
120Ω
RX232
RX485
DOUT1
DOUT2
28701 F34
RIN1
RIN2
CH2
C
LB
L
Y
A
B
Z
28701f
3k