MC145193F Freescale Semiconductor, MC145193F Datasheet - Page 19

• Manufacturer Part Number: MC145193F
• Manufacturer: Freescale Semiconductor

Specifications of MC145193F

• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Package Type: SO
• Pin Count: 20
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Supplier Unconfirmed

(A)
NOTE:
(B)
NOTE:
DEFINITIONS:
is the frequency at the phase detector input. Larger n values result in faster loop lock times and, for similar sideband filtering, higher f R –related
VCO sidebands.
filtering may be active or passive.
RECOMMENDED READING:
MOTOROLA WIRELESS SEMICONDUCTOR
SOLUTIONS – RF AND IF DEVICE DATA
Gardner, Floyd M., Phaselock Techniques (second edition). New York, Wiley–Interscience, 1979.
Manassewitsch, Vadim, Frequency Synthesizers: Theory and Design (second edition). New York, Wiley–Interscience, 1980.
Blanchard, Alain, Phase–Locked Loops: Application to Coherent Receiver Design. New York, Wiley–Interscience, 1976.
Egan, William F., Frequency Synthesis by Phase Lock. New York, Wiley–Interscience, 1981.
Rohde, Ulrich L., Digital PLL Frequency Synthesizers Theory and Design. Englewood Cliffs, NJ, Prentice–Hall, 1983.
Berlin, Howard M., Design of Phase–Locked Loop Circuits, with Experiments. Indianapolis, Howard W. Sams and Co., 1978.
Kinley, Harold, The PLL Synthesizer Cookbook. Blue Ridge Summit, PA, Tab Books, 1980.
Seidman, Arthur H., Integrated Circuits Applications Handbook , Chapter 17, pp. 538–586. New York, John Wiley & Sons.
Fadrhons, Jan, “Design and Analyze PLLs on a Programmable Calculator,” EDN . March 5, 1980.
AN535, Phase–Locked Loop Design Fundamentals, Motorola Semiconductor Products, Inc., 1970.
AR254, Phase–Locked Loop Design Articles, Motorola Semiconductor Products, Inc., Reprinted with permission from Electronic Design,
AN1253, An Improved PLL Design Method Without n and , Motorola Semiconductor Products, Inc., 1995.
For a nominal design starting point, the user might consider a damping factor
Either loop filter (A) or (B) is frequently followed by additional sideband filtering to further attenuate f R –related VCO sidebands. This additional
1987.
For (A), using K in amps per radian with the filter’s impedance transfer function, Z(s), maintains units of volts per radian for the detector/filter
combination. Additional sideband filtering can be accomplished by adding a capacitor C across R. The corner c = 1/RC should be chosen
such that n is not significantly affected.
For (B), R 1 is frequently split into two series resistors; each resistor is equal to R 1 divided by 2. A capacitor C C is then placed from the midpoint
to ground to further filter the error pulses. The value of C C should be such that the corner frequency of this network does not significantly
affect n .
N = Total Division Ratio in Feedback Loop
K (Phase Detector Gain) = I PDout / 2 amps per radian for PD out
K (Phase Detector Gain) = V PD / 2 volts per radian for V and R
K VCO (VCO Transfer Function) =
R
V
PD out
R 1
R 1
R
C
R 2
C
PHASE–LOCKED LOOP — LOW–PASS FILTER DESIGN
Freescale Semiconductor, Inc.
VCO
For More Information On This Product,
2
R 2
–
+
V VCO
A
f VCO
C
radians per volt
Go to: www.freescale.com
VCO
MC145193
0.7 and a natural loop frequency n
Z(s) =
Assuming Gain A is very large, then:
F(s) =
n =
n =
=
=
R 2 sC + 1
R
2
1 + sRC
n R 2 C
R 1 sC
sC
2
K K VCO
K K VCO
NCR 1
K
NC
K VCO C
N
(2 f R / 50) where f R
=
n RC
2
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