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©2018 Integrated Device Technology, Inc
September 12, 2018
8A3xxxx Family Programming Guide
DPLL_0.DPLL_FASTLOCK_CFG_1
Configure pre fast acquisition timer, damping factor.
LOCK_ACQ_PHASE_SNA
P_EN[1]
R/W
0
Enable phase snap for LOCKACQ state.
When lock_acq_ol_pull_in_en is also enabled, instead phase snap, open loop
phase pull-in will be performed.
0 = disabled
1 = enabled
LOCK_ACQ_FREQ_SNAP
_EN[0]
R/W
0
Enable frequency snap for LOCKACQ state.
0 = disabled
1 = enabled
Table 206: DPLL_0.DPLL_FASTLOCK_CFG_1 Bit Field Locations and Descriptions
Offset
Address
(Hex)
DPLL_0.DPLL_FASTLOCK_CFG_1 Bit Field Locations
D7
D6
D5
D4
D3
D2
D1
D0
024h
PRE_FAST_ACQ_TIMER[7:4]
DAMP_FTR[3:0]
DPLL_0.DPLL_FASTLOCK_CFG_1 Bit Field Descriptions
Bit Field Name
Field Type Default Value
Description
PRE_FAST_ACQ_TIMER[
7:4]
R/W
0
Pre-fast acquisition stage timer.
If the value n > 0, the DPLL opens up the bandwidth to the maximum for a
duration of 2^(n-1) milliseconds.
If the value n = 0, then pre-fast-acquisition stage is disabled.
Only applied to LOCKACQ state.
DAMP_FTR[3:0]
R/W
0
DPLL damping factor for fast acquisition stage.
0 = 1.002, 0.02 dB, overdamp;
1 = 1.006, 0.05 dB, < 0.05dB;
2 = 1.008, 0.07 dB, < 1%;
3 = 1.012, 0.10 dB, < 0.1dB;
4 = 1.015 , 0.13 dB, < 2%;
5 = 1.022, 0.19 dB, < 0.2dB;
6 = 1.053 , 0.45 dB, < 0.5dB;
7 = 1.172 , 1.38 dB, underdamp;
DPLL_0.DPLL_FASTLOCK_CFG_0 Bit Field Descriptions
Bit Field Name
Field Type Default Value
Description