Electrical Specifications
CGM Acquisition/Lock Time Specificati ons
MC68HC908MR16/MC68HC908MR32 — Rev. 4.0 Advance Information
MOTOROLA Electrical Specifications 377
22.13 CGM Acquisition/Lock Time Specifications
Description Symbol Min Typ Max Notes
Filter capacitor multiply factor CFACT 0.0154 — F/sV
Acquisition mode time factor KACQ 0.1135 — V
Tracking mode time factor KTRK 0.0174 — V
Manual mode time to stable tACQ (8*VDDA)/
(fXCLK*KACQ) If CF chosen
correctly
Manual stable to lock time tAL (4*VDDA)/
(fXCLK*KTRK)If CF chosen
correctly
Manual acquisition time tLock tACQ+tAL
Tracking mode entry frequency
tolerance TRK 0—
±3.6%
Acquisition mode entry frequency
tolerance ACQ ±6.3% ±7.2%
Lock entry frequency tolerance Lock 0—
±0.9%
Lock exit frequency tolerance UNL ±0.9% ±1.8%
Reference cycles per acquisition
mode measurement nACQ —32
Reference cycles per tracking
mode measurement nTRK 128 —
Automatic mode time to stable tACQ nACQ/fXCLK (8*VDDA)/
(fXCLK*KACQ) If CF chosen
correctly
Automatic stable to lock time tAL nTRK/fXCLK (4*VDDA)/
(fXCLK*KTRK)If CF chosen
correctly
Automatic lock time tLock tACQ+tAL
PLL jitter (deviation of average bus
frequency over 2 ms) fJ0—
± (fXCLK)
*(0.025%)
*(N/4)
N = VCO
freq. mult.