MC68HC08AS32 Datasheet, PDF (120/394 Pages) Motorola, Inc – M68HC08 Family of 8-bit microcontroller units (MCUs)

Clock Generator Module (CGM)
Refer to 8.4.2 Phase-Locked Loop Circuit (PLL) for the value of f_RDV.
Also, since the average frequency over the entire measurement period
must be within the specified tolerance, the total time usually is longer
than t_Lock as calculated above.
In manual mode, it is usually necessary to wait considerably longer than
t_Lock before selecting the PLL clock (see 8.4.3 Base Clock Selector
Circuit), because the factors described in 8.10.2 Parametric
Influences on Reaction Time can slow the lock time considerably.
Advance Information
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Clock Generator Module (CGM)
MC68HC08AS32 — Rev. 3.0
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