BU2624AF Datasheet, PDF (8/9 Pages) Rohm – PLL frequency synthesizer for tuners

Audio ICs
Frequency counter and unlock detection
(1) When CT = 1: Frequency count and unlock detection are carried out.
BU2624AF
(2) When CT = 0 and GT = 1: Only unlock detection is carried out.
Explanation of CD terminal
When frequency measurement or unlock detection is fin-
ished, the CD terminal goes to LO to indicate that the
count and unlock detection have finished.
It also synchronizes with CK to output counter data.
When the next data is input, it goes to HI.
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