Data Sheet
ADM3483/ADM3485/ADM3488/ADM3490/ADM3491
LINE LENGTH vs. DATA RATE
The RS-485 and RS-422 standards cover line lengths up to 4000 feet. For line lengths greater than 4000 feet, see Figure 36.
MAXIMUM NUMBER OF TRANSCEIVERS ON BUS = 32
ADM3483/
ADM3485
ADM3483/
ADM3485
V
CC
R1
R
R
RO
RE
DE
DI
RO
RE
DE
DI
A
A
R
R
T
T
B
B
D
D
R2
A
B
A
B
ADM3483/
ADM3485
ADM3483/
ADM3485
R
R
D
D
RO RE DE DI
RO RE DE DI
NOTES
1. R IS EQUAL TO THE CHARACTERISTIC IMPEDANCE OF THE CABLE.
T
Figure 32. ADM3483/ADM3485 Typical Half-Duplex RS-485 Network
MAXIMUM NUMBER OF NODES = 32
V
T
CC
MASTER
R
SLAVE
D
R1
A
B
Z
Y
Z
RO
RE
DE
DI
DI
R
R
T
DE
RE
RO
R1
R2
B
A
R
R
T
T
D
R
Y
V
CC
R2
ADM3491
ADM3491
A
B
Z
Y
A
B
Z
Y
SLAVE
SLAVE
R
R
D
D
ADM3491
ADM3491
RO RE DE DI
RO RE DE DI
NOTES
1. R IS EQUAL TO THE CHARACTERISTIC IMPEDANCE OF THE CABLE.
T
Figure 33. ADM3491 Typical Full-Duplex RS-485 Network
Rev. E | Page 15 of 20
ROCHESTER [ Rochester Electronics ]
