MB15C03
Table.1 Phass comparator inputs/output relationships
FC
“L”
“H”
fr > fp
H
L
fr = fp
Z
Z
fr < fp
L
H
(b) Phase comparator input/output waveforms
The phase comparator outputs logic levels summarized in Table 1, according to the phase error between fr
and fp.
The pulse width of the phase comparator outputs are identical and equal to the phase error between fr and
fp as shown in Figure 1.
Figure 1 Phase comparator input/output waveforms
fr
fp
When FC = “L”
DO
When FC = “H”
DO
High Z
High Z
High Z : High impedance state
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