BU2615S Datasheet, PDF (8/9 Pages) Rohm – PLL frequency synthesizer for tuners

Audio ICs
FHow the frequency counter and unlock detection circuit operate
(1) When CT = 1: Frequency count and unlock detec-
tion are carried out.
BU2615S / BU2615FS
(2) When CT = 0 and GT = 1: Only unlock detection is
carried out.
FExplanation 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 syn-
chronizes with CK to output counter data. When the next
data is input, it goes to HI.
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