AN178 Philips, AN178 Datasheet
AN178
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AN178 Summary of contents
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... AN178 Modeling the PLL DataSheet4U.com 4 DataSheet U .com INTEGRATED CIRCUITS DataSheet4U.com DataSheet4U.com 1988 Dec ...
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... zero; hence, the the instantaneous frequency separation between the is the phase difference between e the phase comparator output would be a sinusoidal beat note and were sufficiently close DataSheet4U.com Application note AN178 + ) but I O (2) and O ...
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... V (t) o where phase error) characteristics of interest. The product of these two signals is an output voltage given by V (t) e where K amplitude of v signal V l locked loop ( 3 Application note AN178 (t), from the VCO. Refer to Figure 1 and o V sin sin ( and ...
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... RADIAN VOLT s) K RADIANS o S VOLT SEC. Figure 4. Linear Model of PLL System and K for all of Philips Semiconductors d o and Ko for a loop under lock. The function of the Khron-Hite DataSheet4U.com Application note AN178 (13) is the (14) contains and i o (S) V (S) D VOLTS A VOLT SL01014 ...
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... Often it is convenient to specify rad O K O(norm value at any desired free-running frequency then can any o(norm This is further illustrated in the article F(s) V T(s) s T(s) H(s) 1 T(s) DataSheet4U.com Application note AN178 SL01015 (15) (16) (17) (18) (19) ...
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... Since there is no low-pass filter in this case, sum (20) frequency components are also present at the phase comparator output and must be filtered outside of the loop if the difference frequency component (demodulated FM measured. DataSheet4U.com Figure 6. Root Locus and Frequency Response Plots 6 Application note AN178 SL01016 DataSheet4U.com ...
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... F the magnitude of the low-pass filter transfer function C . Solution of Equation 24 frequently involves a “trial Figure 7. Typical PLL Frequency-to-Voltage Transfer Characteristics DataSheet4U.com Application note AN178 (23) (24) (25) (26) SL01017 ...
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... DataSheet4U.com Application note AN178 2 (35 (36) (37) SL01018 (38) (39) (40) (41) (42) (43) (44) (45) ...
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... DataSheet4U.com Application note AN178 (49) (50) 2 (51) 2 (52) SL01021 (53) (54) (55) ...
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... the first term, the loop can lock when (t) V cos ( constant) also a function of the input amplitude V d DataSheet4U.com Application note AN178 t ) (59) k (60) t] (61 the first O is driven closer O (62) ...
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... If locking to even harmonics is desired, the duty cycle of the input and VCO signals terms may be k must be shifted away from the symmetrical to generate substantial, even harmonic, content. 11 Application note AN178 the quadraturephase detector output is then sin ...
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... This may be appreciated when we review the following factors which influence lock-up time. a. Input phase b. Low-pass filter characteristic c. Loop damping d. Deviation of input frequency from center frequency e. In-band input amplitude f. Out-band signals and noise g. Center frequency 12 DataSheet4U.com Application note AN178 ...
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... Thus, whenever a system can be operated at a higher frequency, lock will typically take place faster. Also, in systems where different frequencies are being detected, the higher frequencies, on the average, will be detected before the lower frequencies. DataSheet4U.com Application note AN178 is a factor in the ...
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... The faster the FM modulation in relation to the center frequency, the for the VCO at o lower the value of the capacitor in the low pass filter must be for 14 DataSheet4U.com Application note AN178 SL01025 ...
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... Figure 19 tabulates some approximate relationships. 15 Figure 17. Measurement Setup for Display of PLL Transient Response , K , and the lowpass filter. Since are functions of the free-running frequency and input 0.28. DataSheet4U.com Application note AN178 SL01027 o (68 ...
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... Dec 4 DataSheet U .com a. Underdamped with 0.28 Damped with c. Overdamped with 10 DataSheet4U.com b. Ratio of Peak Amplitude to Low Frequency Amplitude of Error Voltage From Modulating Frequency Response Figure 19. Estimating the Damping in a Second-Order PLL 16 b. Critically 1.0 d. Highly Overdamped with > 10 DataSheet4U.com Application note AN178 SL01028 SL01029 ...
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... Philips Semiconductors Modeling the PLL DataSheet4U.com 1988 Dec 4 DataSheet U .com NOTES DataSheet4U.com 17 DataSheet4U.com Application note AN178 ...
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... Sunnyvale, California 94088–3409 Telephone 800-234-7381 DataSheet4U.com 1988 Dec 4 DataSheet U .com DataSheet4U.com Philips Semiconductors and Philips Electronics North America Corporation register eligible circuits under the Semiconductor Chip Protection Act. Copyright Philips Electronics North America Corporation 1988 18 DataSheet4U.com Application note AN178 All rights reserved. Printed in U.S.A. ...