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PRELIMINARY
PM4332 TE-32
DATA SHEET
PMC-2011402
ISSUE 1
HIGH DENSITY 32 CHANNEL T1/E1/J1 FRAMER
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR THE INTERNAL USE OF ITS CUSTOMERS
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jittered data and stores the stream in a FIFO timed to the associated clock. The
jitter attenuated data emerges from the FIFO timed to the jitter attenuated clock.
In the receive jitter attenuator, the jitter attenuated clock is referenced to the
demultiplexed or demapped tributary receive clock. In the transmit jitter
attenuator, the jitter attenuated transmit tributary clock feeding the line side SBI
interface may be referenced to either the data stream, the CTCLK primary input,
or the tributary receive clock.
Jitter Characteristics
The jitter attenuators provide excellent jitter tolerance and jitter attenuation while
generating minimal residual jitter. In T1 mode, each jitter attenuator can
accommodate up to 48 UIpp of input jitter at jitter frequencies above 4 Hz. For
jitter frequencies below 4 Hz, more correctly called wander, the tolerance
increases 20 dB per decade. In E1 mode each jitter attenuator can
accommodate up to 48 UIpp of input jitter at jitter frequencies above 5 Hz. For
jitter frequencies below 5 Hz, more correctly called wander, the tolerance
increases 20 dB per decade. In most applications, each jitter attenuator will limit
jitter tolerance at lower jitter frequencies only. The jitter attenuator meet the
stringent low frequency jitter tolerance requirements of AT&T TR 62411 and ITU-
T Recommendation G.823, and thus allow compliance with these standards and
the other less stringent jitter tolerance standards cited in the references.
The jitter attenuators exhibit negligible jitter gain for jitter frequencies below 3.4
Hz, and attenuates jitter at frequencies above 3.4 Hz by 20 dB per decade in T1
mode. It exhibits negligible jitter gain for jitter frequencies below 5 Hz, and
attenuates jitter at frequencies above 5 Hz by 20 dB per decade in E1 mode. In
most applications the jitter attenuators will determine jitter attenuation for higher
jitter frequencies only. Wander, below 10 Hz for example, will essentially be
passed unattenuated through the jitter attenuators. Jitter, above 10 Hz for
example, will be attenuated as specified, however, outgoing jitter may be
dominated by the waiting time jitter introduced by mapping into SBI. The jitter
attenuator allows the implied T1 jitter attenuation requirements for a TE or NT1
given in ANSI Standard T1.408, and the implied jitter attenuation requirements for
a type II customer interface given in ANSI T1.403 to be met. The jitter attenuator
meets the E1 jitter attenuation requirements of the ITU-T Recommendations
G.737, G.738, G.739 and G.742.
Jitter Tolerance
Jitter tolerance is the maximum input phase jitter at a given jitter frequency that a
device can accept without exceeding its linear operating range, or corrupting
data. For T1 modes the jitter attenuator input jitter tolerance is 48 Unit Intervals
peak-to-peak (UIpp) with a worst case frequency offset of 278 Hz. For E1 modes