DS26519GA2 Maxim Integrated, DS26519GA2 Datasheet - Page 97

• Manufacturer Part Number: DS26519GA2
• Description: Network Controller & Processor ICs
• Manufacturer: Maxim Integrated

Specifications of DS26519GA2

• Part # Aliases: 90-26519-0A2

9.12.3 Receiver
9.12.3.1
The DS26519 contains 16 receivers. The termination circuit provides an analog switch that powers up in the open
setting, providing high impedance to the receive line side. This is useful for redundancy applications and hot
swapability.
Three termination methods are available:
See the
110Ω, or 120Ω termination by setting the appropriate RIMPM[1:0] bits. These bits must be configured to match line
impedance even if internal termination is disabled.
Table 9-41. Receive Impedance Control
Figure 9-23
external resistor, R
Figure 9-23. Receive LIU Termination Options
The device couples to the receive E1 or T1 twisted pair (or coaxial cable in 75Ω E1 applications) via a 1:1 or 2:1
transformer. See
Receive sensitivity is configurable by setting the appropriate RSMS[1:0] bits (LRCR).
LRISMR.
RIMPON
•
•
0
0
1
1
Partially internal impedance matching with a 120Ω external resistor, normally connected from RTIPEn to
RRINGn.
External resistor termination, internal termination disabled.
LRISMR
shows a diagram of the switch control of termination. If internal impedance match is disabled, the
Receive Internal Termination
LRISMR.
REXTON
Table 9-40
and
T
, must match the line impedance.
0
1
0
1
RECEIVE LIU
LRCR
for transformer details.
Highimpedance.
Internal impedance disabled, RTIPEn connected to RTIPn.
Internal impedance enabled, RTIPEn disconnected from RTIPn.
Internal impedance enabled, RTIPEn connected to RTIPn.
registers for more details. Internal impedance match is configurable to 75Ω, 100Ω,
R
R
RRINGn
RTIPn
RTIPEn
R
LRISMR.REXTON
T
LRISMR.RIMPON
97 of 310
SETTING
TFR
1:1
DS26519 16-Port T1/E1/J1 Transceiver
Rx LINE