ACS8525AT Semtech, ACS8525AT Datasheet - Page 31

• Manufacturer Part Number: ACS8525AT
• Manufacturer: Semtech

Specifications of ACS8525AT

• Lead Free Status / RoHS Status: Compliant

Figure 8 Automatic Mode Control State Diagram (DPLL1)
Note...The state diagram above is for DPLL1 only, and the 3-bit state value refers to the register sts_operating Reg. 09 Bits
[2:0] DPLL1_operating _mode. By contrast, the DPLL2 has only automatic operation and can be in one of only two possible
states: “Instantaneous Automatic Holdover” with zero frequency offset (its start-up state), or “Locked”. The states of DPLL2
are not configurable by the User and there is no “Free-run” state.
Revision 1.00/September 2007 © Semtech Corp.
ADVANCED COMMS & SENSING
(higher-priority ref valid
& in revertive mode) or
(15) valid standby ref
[main ref invalid or
out of lock >100s]
wait for up to 100s
(10) selected source
Pre-locked2
(state 101)
&
phase locked
(higher-priority ref valid
& in revertive mode) or
(4) valid standby ref
[main ref invalid or
out of lock > 100s]
(1) Reset
&
(higher priority ref valid
(12) valid standby ref
or out of lock >100s)
(3) no valid standby ref
& in revertive mode)]
or out of lock > 100s
(9) valid standby ref
[main ref invalid or
(main ref invalid
(main ref invalid
&
&
&
(13) no valid standby ref
(14) all refs evaluated
at least one ref valid
or out of lock >100s)
wait for up to 100s
wait for up to 100s
within 100s
(5) selected ref
(main ref invalid
(8) phase
regained
phase locked
(state 001)
(state 110)
(state 100)
(state 111)
Pre-locked
Lost-phase
select ref
Free-run
keep ref
Locked
&
&
FINAL
Page 31
(7) phase lost
(2) all refs evaluated
at least one ref valid
on main ref
(11) no valid standby ref
or out of lock >100s)
(main ref invalid
&
&
F8525D_018AutoModeContStateDia_01
reference when that reference has lost phase
Reference sources are flagged as valid when
active, in-band and have no phase alarm set.
whilst being used as the main reference. The
A source is considered to have phase locked
when it has been continuously in phase lock
Only the main source is checked for phase.
micro-processor can reset the phase lock
All sources are continuously checked for
(6) no valid standby ref
A phase lock alarm is only raised on a
main ref invalid
Digital Holdover
for between 1 and 2 seconds.
(state 010)
select ref
activity and frequency
&
ACS8525A LC/P
alarm.
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