pef22504 Infineon Technologies Corporation, pef22504 Datasheet - Page 94

• Manufacturer Part Number: pef22504
• Description: Quad E1/t1/j1 Line Interface Component For Long- And Short-haul Applications Pef 22504 E, Pef 22504 Ht, Version 2.1
• Manufacturer: Infineon Technologies Corporation

Figure 29
The DCO-R reference clock is watched: If one, two or three clock periods of the 2.048 MHz (1.544 MHz in T1/J1
mode) clock at pin SYNC or RCLKI (in single rail digital line interface mode) are missing the DCO-R regulates it´s
output frequency. If four or more clock periods are missing
•
•
The receive jitter attenuator works in two different modes, selected by the multiplexer “C” in
•
•
The following table
Data Sheet
The DCO-R circuitry is automatically centered to the nominal bit rate if the center function of DCO-R is enabled
by CMR2.DCF = ´0´.
The actual DCO-R output frequency is “frozen” if the center function of DCO-R is disabled by CMR2.DCF = ´1´.
Slave mode: In slave mode (LIM0.MAS = ´0´) the DCO-R is synchronized on the recovered route clock. In case
of loss of signal (LOS) the DCO-R switches automatically to Master mode. The frequency at the pin SYNC
must be 2.048 MHz (1.544 MHz). If bit CMR1.DCS is set automatic switching from the recovered route clock
to SYNC is disabled.
Master mode: In master mode (LIM0.MAS = ´1´) the DCO-R is in free running mode if no clock is supplied on
pin SYNC. If an external clock on the SYNC input is applied, the DCO-R synchronizes to this input. The
external frequency can be 2.048 MHz (1.544 MHz) for IPC.SSYF = ´0´ or 8.0 kHz for IPC.SSYF = ´1´.
Principle of Configuring the DCO-R and DCO-X Corner Frequencies
switches
corner
frequency to
0.2 Hz in E1
sets corner
frequency to
2 Hz in E1
LIM2.SCF for DCO-R,
CMR6.SCFX for DCO-X
Table 24
Reset
Table
ECFAX for DCO-X, ECFAR for DCO-R
shows this modes with the corresponding synchronization sources.
„Corner
frequency
adjust“
P
corner
frequency
2 or 0.2 Hz
in E1
I
CFAX (for DCO-X) CFAR (for DCO-R)
DCO-R
(DCO-X)
MUX
P
I
Table
P
LIM2,
CMR6
corner
frequency
range 2 …
0.2 Hz in E1
I
MUX
P
94
I
P
CMR2
corner
frequency
range 8 …
0.2 Hz
IAX (for DCO-X)
CMR5
CMR3
I
IAR (for DCO-R)
QLIU_DCO_X_adjust_2
Functional Description
CMR4
DCOCOMPN
Rev. 1.3, 2006-01-25
Figure
CMR6
QuadLIU
PEF 22504
22:
TM