lc72135m Sanyo Semiconductor Corporation, lc72135m Datasheet - Page 19

• Manufacturer Part Number: lc72135m
• Description: Pll Frequency Synthesizer For Electronic Tuning
• Manufacturer: Sanyo Semiconductor Corporation

Unlock Detection Timing
1. Unlock Detection Determination Timing
Unlocked state detection is performed in the reference frequency (fref) period (interval). Therefore, in principle,
unlock determination requires a time longer than the period of the reference frequency. However, immediately after
changing the divisor N (frequency) unlock detection must be performed after waiting at least two periods of the
reference frequency.
For example, if fref is 1 kHz, i.e., the period is 1 ms, after changing the divisor N, the system must wait at least 2 ms
before checking for the unlocked state.
Figure 1 Unlocked State Detection Timing
Figure 2 Circuit Structure
LC72135M
No. 5175-19/24