AK1590 Datasheet, PDF (15/36 Pages) Asahi Kasei Microsystems – 1GHz Delta-Sigma Fractional-N Frequency Synthesizer

[AK1590]
5. Lock Detect (LD) Signal
In AK1590, “lock detect” output can be selected by D[11] = {LD} in <Address3>. When D[11] is set to “1", the phase
detector output provides a phase detection status as an analog level (comparison result). This is called “Analog Lock
Detect”.
When D[11] is set to “0”, the lock detect signal outputs according to the on-chip logic. This is called “Digital Lock Detect”.
5.1 Analog Lock Detect
In analog lock detect, the phase detector output comes from [LD] pin.
Reference clock
PFD clock
VCO divide clock
Phase detector output
LD output
Fig. 7 Analog Lock Detect Operation
MS1478-E-01
15
2013/2