HCF4046B_01 Datasheet, PDF (9/12 Pages) STMicroelectronics – MICROPOWER PHASE-LOCKED LOOP

HCF4046B
DESIGN INFORMATION This information is a guide for approximating the value of external components
in a Phase-Locked-Loop system. The selected external components must be within the following ranges:
5KΩ ≤ R₁, R₂, R_S ≤ 1MΩ C₁ ≥ 100pF at V_DD ≥ 5V C₁ ≥ 50pF at V_DD ≥ 10V
CHARACTERISTICS
USING PHASE COMPARATOR I
VCO WITHOUT
OFFSET R2=∞
VCO WITH
OFFSET
USING PHASE COMPARATOR II
VCO WITHOUT
OFFSET R2=∞
VCO WITH
OFFSET
VCO Frequency
For No Signal Input
Frequency Lock Range,
2f_L
VCO in PLL System will Adjust to Centre VCO in PLL System will Adjust to Lowest
Frequency f_o
Operating Frequency f_o
2 f_L = Full VCO Frequency Range
2fL = f_max - f_min
Frequency Lock Range,
2f_C
Loop filter Component
Section
f_C = f_L
Phase Angle Between
SIgnal and Comparator
Locks on Harmonics of
Centre Frequency
Signal Input Nose Rejec-
tion
90° at Centre frequency (f_O), approximating
0° and 180° at ends of lock range (2 f_L)
Yes
High
For further information, see
(1) F. Gardner, "Phase-Lock Techniques" John Wiley and Sons, New York, 1966
(2) G.S. Mosckytz "miniaturized RC filters using phase Lockedloop" BSTJ May 1965
Always 0° in lock
No
Low
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