ACS8520T Semtech, ACS8520T Datasheet - Page 98

• Manufacturer Part Number: ACS8520T
• Description: Synchronous Equipment Timing Source (SETS) for Stratum 3/4E/4 and SMC Systems
• Manufacturer: Semtech

Address (hex):
Address (hex):
Revision 3.02/October 2005 © Semtech Corp.
ADVANCED COMMUNICATIONS
Register Name
Register Name
Bit No.
Bit No.
Bit 7
[7:4]
[3:0]
Bit 7
[7:4]
[3:0]
current_soft_frequency_alarm_threshold
49
4A
cnfg_freq_mon_threshold
Description
soft_frequency_alarm_threshold
Threshold to trigger the soft frequency alarms in the
sts_reference_sources registers.
This is only used for monitoring.
hard_frequency_alarm_threshold
Threshold to trigger the hard frequency alarms in
the sts_reference_sources registers, which can
cause a reference source rejection.
cnfg_current_freq_mon_
threshold
Description
current_soft_frequency_alarm_threshold
Threshold to trigger the soft frequency alarm in the
sts_reference_sources register applying to the
currently selected source.The currently selected
source can be monitored for frequency using
different limits to all other sources.
current_hard_frequency_alarm_threshold
Threshold to trigger the hard frequency alarm in the
sts_reference_sources register applying to the
currently selected source.
soft_frequency_alarm_threshold
Bit 6
Bit 6
Bit 5
Bit 5
Description
Description
Bit 4
Bit 4
FINAL
Page 98
(R/W) Register to set both the
hard and soft frequency alarm
limits for the monitors on the
input reference sources.
(R/W) Register to set both the
hard and soft frequency alarm
limits for the monitors on the
currently selected reference
source.
Bit Value
Bit Value
Bit 3
Bit 3
-
-
current_hard_frequency_alarm_threshold
Value Description
To calculate the limit in ppm, add one to the 4-bit
value in the register, and multiply by 3.81 ppm. The
limit is symmetrical about zero. A value of 0010 bin
corresponds to an alarm limit of ±11.43 ppm.
To calculate the limit in ppm, add one to the 4-bit
value in the register, and multiply by 3.81 ppm. The
limit is symmetrical about zero. A value of 0011 bin
corresponds to an alarm limit of ±15.24 ppm.
Value Description
To calculate the limit in ppm, add one to the 4-bit
value in the register, and multiply by 3.81 ppm. The
limit is symmetrical about zero. A value of 0010 bin
corresponds to an alarm limit of ±11.43 ppm.
To calculate the limit in ppm, add one to the 4-bit
value in the register, and multiply by 3.81 ppm. The
limit is symmetrical about zero. A value of 0011 bin
corresponds to an alarm limit of ±15.24 ppm.
hard_frequency_alarm_threshold
Bit 2
Bit 2
Default Value
Default Value
ACS8520 SETS
Bit 1
Bit 1
DATASHEET
www.semtech.com
0010 0011
0010 0011
Bit 0
Bit 0