Typical Performance Characteristics (Continued)
VHC4046 Typical VCO Linearity vs R1 & C1
VHC4046 Typical VCO Linearity vs R1 & C1
VCO WITHOUT OFFSET
R2 = ∞
VCO WITH OFFSET
Comparator I
R2=∞
–Given: fO
–Use fO with curve titled
center frequency vs R1, C
to determine R1 and C1
R2≠∞
–Given: fO and fL
–Calculate fMIN from the
equation fMIN = fO − fL
–Use fMIN with curve titled
offset frequency vs R2, C
to determine R2 and C1
–Calculate fMAX/fMIN from
the equation fMAX/fMIN =
fO + fL/fO − fL
–Use fMAX/fMIN with curve
titled fMAX/fMIN vs R2/R1
to determine ratio R2/R1
to obtain R1
Comparator II & III
R2=∞
–Given: fMAX
–Calculate fO from the
equation fO = fMAX/2
–Use fO with curve titled
center frequency vs R1, C
to determine R1 and C1
R2≠∞
–Given: fMIN and fMAX
–Use fMIN with curve titled
offset frequency vs R2,
C to determine R2 and C1
–Calculate fMAX/fMIN
–Use fMAX/fMIN with curve
titled fMAX/fMIN vs R2/R1
to determine ratio R2/R1
to obtain R1
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