What is IC LM565?
What is an LM565 IC? The LM565 is a general-purpose PLL or phase-locked loop IC which includes a constant, extremely linear VCO (voltage controlled oscillator) for less deformation FM demodulation & a phase detector with double balanced & superior carrier control.
How PLL is used in FM demodulation?
The PLL uses the concept of minimising the difference in phase between two signals: a reference signal and a local oscillator to replicate the reference signal frequency. Using this concept it is possible to use PLLs for many applications from frequency synthesizers to FM demodulators, and signal reconstitution.
What is the function of the ne565?
LM565 is a general purpose PLL (Phase Locked Loop) IC designed for demodulation, frequency multiplication and frequency division. The device mainly consists of two components, one is voltage controller oscillator and other is phase detector….Pin Configuration.
| Pin | Name | Function |
|---|---|---|
| 14 | NC | No connection |
Is PLL used in FM demodulator?
Further, PLL is also useful for demodulating FM signals in presence of large noise and low signal power. This means that, PLL is most suitable for use in space vehicle-to-earth data links or where the loss along the transmission line or path is quite large. Recently, it has found application in commercial FM receivers.
How does a voltage controlled oscillator work?
A voltage-controlled oscillator is an oscillator with an output signal whose output can be varied over a range, which is controlled by the input DC voltage. It is an oscillator whose output frequency is directly related to the voltage at its input. The oscillation frequency varies from few hertz to hundreds of GHz.
What is the use of VCO in PLL?
The VCO generates the output signal. It is maintained at the setpoint frequency by the PLL and locked to the reference frequency. The reference frequency is typically supplied by a very accurate quartz oscillator.
How does FM demodulator work?
FM demodulation basics In any radio that is designed to receive frequency modulated signals there is some form of FM demodulator or detector. This circuit takes in frequency modulated RF signals and takes the modulation from the signal to output only the modulation that had been applied at the transmitter.
What is free running frequency?
The VCO is a special type of oscillator that has a frequency controlled by an applied voltage. The frequency of the VCO without any control signal applied is called the free- running frequency, f0.
What circuit is used for FM demodulation?
Phase Locked Loop (PLL)
The FM demodulator is done with the help of a circuit called Phase Locked Loop (PLL). A PLL should have basic functional blocks like Voltage Controlled Oscillator (VCO), Phase comparator, Low Pass Filter (LPF) and Source follower.
How do you control the frequency of an oscillator?
By varying the total impedance of each oscillator oscillatory network, frequencies of oscillations are controlled using potentiometers. The main advantage of the proposed circuits is that both the amplitude and frequency of the waveforms generated can be independently controlled.
What is the purpose of VCO?
This is the function of voltage controlled oscillators (VCOs). These devices are designed to produce an output signal whose frequency varies with the voltage amplitude of an input signal over a reasonable range of frequencies.