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A PLL is different than a VCO. Each has its own use.
Actually a PLL (Phase Locked Loop) contains a VCO (Voltage controlled oscillator).
A VCO is an oscillator whose frequency is related to an input voltage. You can use it when you need a varying frequency that is controlled by a varying voltage. But it is not great at outputting a consistant exact voltage because it is very sensitive to its environment (e.g. temperature).
A PLL will "lock" its output frequency to some input frequency. So it can oscillate at a frequency that is controlled by an input oscillator. Not too useful if the output frequency is the same as the input. But the output frequency can be divided before it is compared to the input. This allows the output frequency to be higher (some multiple of) the input frequency. Once a PLL is "locked on" to an input frequency it can be very stable.
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How does the ic 566 works?
Although the evolution of the PLL began in the early 1930s but its cost outweighted its advantage in the beginning. Today the PLL is even available as a single package, typical examples of which are the Signetic's SE/NE series such as 560, 561, 562, 564, 565 and 567. They only differ in operating frequency range, power requirements, and frequency and bandwidth (BW) adjustment ranges. SE/NE 565 is the most widely employed IC of the series. The device is available as a 14-pin DIP package and as a 10-pin metal can package. Its important electrical characteristics are given below:PLL PIN IDENTIFICATIONCharacteristics of SE/NE 565 PLL ICOperating frequency range : 0.001 Hz to 500 kHz.Operating voltage range : ± 6 to ± 12 V.Input impedance : 10 k Q typically.Output sink current :1mA typically.Output source current : 10 m A typically.Drift in VCO centre frequency with temperature : 300 ppm/ °C typically.Drift in VCO centre frequency with supply voltage : 1.5 %/V maximum.Input level required for tracking : 10 mVrms minimum to 3 V peak-to-peak maximum.Bandwidth adjustment range : < ± 1 to > ± 60 %.NE-SE 565 ICThe block diagram and connection diagram of the SE/NE 565 IC is shown in figure. As shown in the figure, the PLL system consists of a phase detector or comparator (PC), a voltage-controlled oscillator (VCO), an amplifier and R-C combination forming low-pass filter circuit. The input signals are fed to the phase detector through pins 2 and 3 in differential mode. The input signals can be direct-coupled provided that the dc level at these two pins is made same and dc resistances seen from pins 2 and 3 are equal. By shorting pins 4 and 5 output of VCO is supplied back to the phase comparator (PC). The output of PC is ijiternally connected to amplifier, the output of which is available at pins 6 and 7 through a resistor of 3.6 k Q connected internally. A capacitor C2 connected between pins 7 and 10 forms a low-pass filter with 3.6 k Q resistor. The filter capacitor C2 should be large enough so as to eliminate the variations in demodulated output and stabilize the VCO frequency. Voltage available at pin 7 is connected internally to VCO as a control signal. At pin 6 a reference voltage nominally equal to voltage at pin 7 is available allowing both the differ­ential stages to be biased. Pins 1 and 10 are supply pins.The centre frequency of the PLL is determined by the free-running frequency of the VCO which is given asFout = 1.2/4R1C1 Hertzwhere R1 and C1 are external resistor and capacitor connected to pins 8 and 9 respectively, as illustrated in figure. The free-running frequency fout of the VCO is adjusted, externally with Rt and C1, to be at the centre of the input frequency range. Resistor R1 must have a value between 2 and 20 kilo ohm. Capacitor C1 may have any value.The 565 PLL can lock to and track an input signal typically ± 60 % bandwidth with respect to fout as the centre frequency. The lock-range of PLL is given asfL = ± 8fOUT / V Hertzwhere fout is free-running frequency of VCO in Hz and V = (+ V) - (- V) and capture range is given asfC = ± [fL / 2∏ (3.6) (10)3 C2]1/2The lock range usually increases with an increase in input voltage but falls with an increase in supply voltages.
What does the PLL consist of?
PLL stands Phase Locked Loop . It consists of phase detector,low pass filter,voltage controlled oscillator,error amplifier
What are the types of FM demodulator?
Most common nowadays is the quadrature detector. PLL detectors are still common too.
Is nickel a better electrical conductor than gold?
At room temperature, gold will conduct electricity better than almost any other element other than silver.
Does copper conduct electricity better than stainless steel?
Yes. At normal temperatures copper conducts electricity better than almost any other metal; silver is slightly better.
What is the difference between capture range and lock range in Phase lock loop devicee inj?
Lock Range of a PLL is the range of frequencies centered at free running frequency of VCO, around which the PLL can remain in locked state. Capture Range of a PLL is the range of frequencies centered at free running frequency of VCO, around which the PLL can acquire lock-in from an unlocked state. The relation is Capture Range<=Lock Range
Why is the capture range less than the phase locked range?
Once the PLL is in lock, what is the input (or VCO) frequency range for which it can keep itself locked is the lock range. When the PLL is initially not in lock, what frequency range can make the PLL lock is the capture range. Lock range is the parameter you should be interested in if you are looking for it's tracking behavior. But in CP PLLs, both the lock and capture ranges are the same.., limited only by the VCO's tuning range.In modern PLLs capture range and lock range are the same. But by definition these are different and this relaxed usage in journals and books leads to these confusions.Capture range and pull-in range are the same. Both refer to the ability of the system to acquire lock (from an unlocked state) to a frequency. Here the VCO is running at some arbitrary frequency and the disturbance required at the input to make it respond to the input disturbances thereafter is quantified as capture range.While the VCO is responding to the input disturbance (in-lock), the amount of disturbance at the input that will cause the VCO to shun the input and run freely is quantified as lock range.Always lock range is equal to or greater than the capture range.Definitions from the webLock range is defined as the band of frequencies centered on the VCO's natural frequency over which a PLL can maintain frequency lock with an external input signal.Capture range is defined as the band of frequencies centered around the VCO natural frequency where the PLL can initially establish or acquire frequency lock with an external input signal from an unlocked condition.
In what year did Vina Concha Y Toro - VCO - have its IPO?
Vina Concha Y Toro (VCO)had its IPO in 1994.
Who is lucas in pll?
Lucas is part of the A team and a boy on pll
What is the market cap for Vina Concha Y Toro VCO?
As of July 2014, the market cap for Vina Concha Y Toro (VCO) is $1,451,806,122.13.
What does PLL mean in texting?
PLL Stands for Pretty Little Liars .
What is PLL radio?
Simple said it's a radio receiver with PLL (Phase-Locked Loop) function. Go, for example, to http://www.uoguelph.ca/~antoon/gadgets/pll/pll.html for more info about what is PLL.
Is aria a in pll?
yes,aria is "A" in pll,but she only done it to protect her friends
Who is a pll?
CHARLES
What is meant by lock range in pll?
freq range over which PLL can track input variation
What should the PLL clerk do when there is a due-out and an on-hand balance for a PLL line?
Schedule a face to face with SSA
Who should you contact if you lose your AF Form 483?
Your unit VCO
