
Data Sheet
65
Rev. 1.0, 2005-06-02
OctalLIU
TM
PEF 22508 E
Functional Description
The receive clock output RCLK of every channel can be switched between 2 sources, see multiplexer “D” in
If the DCO-R is the source of RCLK the following frequencies are possible: 1.544, 3.088, 6.176, and 12.352 in
T1/J1 mode and 2.048, 4.096, 8.192, and 16.384 MHz in E1 mode. Controlling of the frequency is done by the
register bits CMR4.RS(1:0).
If the recovered clock out (of the clock and data recovery) is the source of RCLK (see multiplexer “D” in
Figure 17), only 2.048 MHz (1.544 MHz) is possible as output frequency.
3.7.9.1
Receive Jitter Attenuation Performance
For E1 the jitter attenuator meets the jitter transfer requirements of the ITU-T I.431 and G.735 to 739 (refer to
For T1/J1 the jitter attenuator meets the jitter transfer requirements of the PUB 62411, PUB 43802, TR-
TSY 009,TR-TSY 253, TR-TSY 499 and ITU-T I.431 and G.703 (refer to Figure 25).
Table 19
Clocking Modes of DCO-R
Mode
Internal LOS
Active
SYNC Input
System Clocks generated by DCO-R
Master
Independent
Fixed to
V
DD
DCO-R centered, if CMR2.DCF = 0. (CMR2.DCF should not be
Master
Independent
2.048 MHz
(E1) or
1.544 MHz
(T1)
Synchronized to SYNC input (external 2.048 MHz or 1.544 MHz,
IPC.SSYF = 0), see also IPC Master
Independent
8.0 kHz
Synchronized to SYNC input (external 8.0 kHz, IPC.SSYF = 1,
CMR2.DCF = 0)
Slave
No
Fixed to
V
DD
Synchronized to recovered line clock
Slave
No
2.048 MHz
(E1) or
1.544 MHz
(T1)
Synchronized to recovered line clock
Slave
Yes
Fixed to
V
DD
CMR1.DCS = 0: DCO-R is centered, if CMR2.DCF = 0.
(CMR2.DCF should not be set)
CMR1.DCS = 1: Synchronized on recovered line clock
Slave
Yes
2.048 MHz
CMR1.DCS = 0: Synchronized to SYNC input
(external 2.048 MHz or 1.544 MHz)
CMR1.DCS = 1: Synchronized on recovered line clock