MC14046BFL2 Ver la hoja de datos (PDF) - ON Semiconductor
Número de pieza
componentes Descripción
Fabricante
MC14046BFL2 Datasheet PDF : 8 Pages
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MC14046B
PCAin
14
@ FREQUENCY f′ 3
PCBin
PHASE
COMPARATOR
2 OR 13
PC1out
OR
PC2out
VCOin
EXTERNAL
LOW−PASS
FILTER
EXTERNAL
÷N
COUNTER
9 SOURCE 10
FOLLOWER
9
VCO
11 12 6
CIA
R1 R2
CI
4
7
CIB
SFout
RSF
VCOout
@ FREQUENCY Nf′ = f
(a)
R3
INPUT
C2
OUTPUT
Ǹ 2fC
[
1
p
2 p fL
R3 C2
Typical Low−Pass Filters
(a)
INPUT
R3
OUTPUT
R4
C2
Typically:
R4 C2
+
6N
fmax
–
N
2pDf
(R3
)
3, 000W)
C2
+
100NDf
fmax2
–
R4 C2
D f = fmax − fmin
NOTE: Sometimes R3 is split into two series resistors each R3 ÷ 2. A capacitor CC is then placed from the midpoint to ground. The value for
CC should be such that the corner frequency of this network does not significantly affect Wn. In Figure B, the ratio of R3 to R4 sets
the damping, R4 ^ (0.1)(R3) for optimum results.
LOW−PASS FILTER
Definitions: N = Total division ratio in feedback loop
Kφ = VDD/π for Phase Comparator 1
Kφ = VDD/4 π for Phase Comparator 2
KVCO
+
2pD
VDD
fVCO
–2V
for
a
typical
design
Wn
^
2 p fr
10
(at phase detector input)
ζ ^ 0.707
Filter A
Ǹ wn +
KfKVCO
NR3C2
Filter B
Ǹ wn +
KfKVCO
NC2(R3 ) R4)
z
+
Nwn
2KfKVCO
F(s)
+
1
R3C2S
)
1
z + 0.5 wn (R3C2 )
N
KfKVCO)
F(s)
+
R3C2S ) 1
S(R3C2 ) R4C2)
)
1
Waveforms
Phase Comparator 1
PCAin
VDD
VSS
Phase Comparator 2
PCAin
VDD
VSS
PCBin
PC1out
VCOin
VOH
VOH
VOL
PCBin
VOL
VOH
VOH
LD
VOL
VOL
VOH
PC2out
VOH
VOL
VOL
VCOin
VOH
VOL
Note: for further information, see:
(1) F. Gardner, “Phase−Lock Techniques”, John Wiley and Son, New York, 1966.
(2) G. S. Moschytz, “Miniature RC Filters Using Phase−Locked Loop”, BSTJ, May, 1965.
(3) Garth Nash, “Phase−Lock Loop Design Fundamentals”, AN−535, Motorola Inc.
(4) A. B. Przedpelski, “Phase−Locked Loop Design Articles”, AR254, reprinted by Motorola Inc.
Figure 3. General Phase−Locked Loop Connections and Waveforms
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