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 SpecificationsDescription 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.