Datasheet

DS26514 4-Port T1/E1/J1 Transceiver
19-5856; Rev 4; 5/11 244 of 305
Register Name:
LRISMR
Register Description:
LIU Receive Impedance and Sensitivity Monitor Register
Register Address:
1007h + (20h x (n - 1)) : where n = 1 to 4
Bit #
7
6
5
4
3
2
1
0
Name
—
RIMPON
—
—
—
RIMPM2
RIMPM1
RIMPM0
Default
0
0
0
0
0
0
0
0
Bit 6: Receive Internal Impedance Match On (RIMPON)
0 =
Receive internal impedance termination is disabled (high impedance).
1 =
Receive internal impedance termination is enabled.
Bits 2 to 0: Receive Impedance Selection (RIMPM[2:0]). These bits are used to select the receive impedance
termination. They must be set according to the cable impedance even if internal termination resistance is disabled
(RIMPON = 0). See
Table 10-22.
Table 10-22. Receive Impedance Selection
RIMPON RIMPRM[2:0]
RECEIVE IMPEDANCE SELECTED (
Ω
)
0
x00
75Ω external termination (no internal impedance match)
0
x01
100Ω external termination (no internal impedance match)
0
x10
110
Ω
external termination (no internal impedance match)
0
x11
120
Ω
external termination (no internal impedance match)
1
000
75
Ω
, with external 120
Ω
resistor
1
001
100
Ω
, with external 120
Ω
resistor
1
010
110
Ω
, with external 120
Ω
resistor
1
011
120
Ω
, with external 120
Ω
resistor
1
100
75
Ω
internal termination
1
101
100Ω internal termination
1
110
110Ω internal termination
1
111
120
Ω
internal termination