ACS8514 View Datasheet(PDF) - Semtech Corporation
Part Name
Description
MFG CO.
ACS8514
Synchronous Equipment Timing Source Partner IC for 2nd T4 DPLL, Accurate Monitoring & Input Extender
Semtech Corporation
'ACS8514' PDF : 86 Pages View PDF
ACS8514 SETS Buddy
ADVANCED COMMS & SENSING FINAL
DATASHEET
Port
Number
I6
I7
I8
I9
I10
I11
I12
I13
I14
Channel
Number (Bin)
0110
0111
Input Port
Technology
PECL/LVDS
PECL default
TTL/CMOS
1000
TTL/CMOS
1001
TTL/CMOS
1010
TTL/CMOS
1011
TTL/CMOS
1100
TTL/CMOS
1101
TTL/CMOS
1110
TTL/CMOS
Frequencies Supported
Up to 155.52 MHz (see Note (ii))
Default (SONET): 19.44 MHz Default (SDH): 19.44 MHz
Up to 100 MHz (see Note 0)
Default (SONET): 19.44 MHz Default (SDH): 19.44 MHz
Up to 100 MHz (see Note 0)
Default (SONET): 19.44 MHz Default (SDH): 19.44 MHz
Up to 100 MHz (see Note 0)
Default (SONET): 19.44 MHz Default (SDH): 19.44 MHz
Up to 100 MHz (see Note 0)
Default (SONET): 19.44 MHz Default (SDH): 19.44 MHz
Up to 100 MHz (see Note 0) Default (Master) (SONET): 1.544 MHz
Default (Master) (SDH): 2.048 MHz Default (Slave) 6.48 MHz
Up to 100 MHz (see Note 0)
Default (SONET): 1.544 MHz Default (SDH): 2.048 MHz
Up to 100 MHz (see Note 0)
Default (SONET): 1.544 MHz Default (SDH): 2.048 MHz
Up to 100 MHz (see Note 0)
Default (SONET): 1.544 MHz Default (SDH): 2.048 MHz
Default
Priority
7
8
9
10
11
12
0
0
0
Notes:
(i) TTL ports (compatible also with CMOS signals) support clock speeds up to 100 MHz, with the highest spot frequency being 77.76 MHz.
The actual spot frequencies are: 2 kHz, 4 kHz, 8 kHz (and N x 8 kHz), 1.544 MHz (SONET)/2.048 MHz (SDH), 6.48 MHz, 19.44 MHz,
25.92 MHz, 38.88 MHz, 51.84 MHz, 77.76 MHz. SONET or SDH input rate is selected via register 34 bit 2, ip_sonsdhb ).
(ii) PECL and LVDS ports support the spot clock frequencies listed above plus 155.52 MHz.
Clock Quality Monitoring
Clock quality is monitored and used to modify the priority
tables of the local and remote ACS8520/30 devices. The
following parameters are monitored continuously for all 14
inputs in parallel :
1. Activity (toggling).
2. Frequency to +/- 3.8 ppm accuracy (this monitoring is
only performed when there is no irregular operation of
the clock or loss of clock condition).
A fine level of frequency monitoring and phase monitoring
is also performed in the two DPLLs. Phase is measured
down to 0.7 degrees with a maximum range of +/- 8191
cycles or +/- 2.9 x 106 degrees. Frequency is measured to
a 0.0003 ppm resolution and +/- 80 ppm range (could be
up to +/- 500 ppm with software enhanced use of the
calibration register (3Ch, 3Dh).
Input ports I1 and I2 carry AMI-encoded composite clocks
which are also additionally monitored by the AMI-decoder
blocks. Loss of signal is declared by the decoders when
either the signal amplitude falls below +0.3 V or there is
no activity for 1 ms.
Any reference source that suffers a loss-of-activity or
clock-out-of-band condition will be declared as
unavailable.
Activity Monitoring
The ACS8514 tests for too much or too little activity via
the activity monitors. The ACS8514 uses a Leaky Bucket
Accumulator, which is a digital circuit which mimics the
operation of an analog integrator, in which input pulses
increase the output amplitude but die away over time.
Such integrators are used when alarms have to be
triggered either by fairly regular defect events, which
Revision 3.00 April 2007 © Semtech Corp.
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