When oscillator. The oscillation frequency of a VCO

When in a wireless application the output
frequency is a function of the input, a tunable oscillator is required, this type of oscillator is known as a voltage
controlled oscillator. The oscillation frequency of a VCO may vary from few
hertz to hundreds of gigahertz.

 

TYPES OF VOC:

1.    Harmonic
oscillators: it produces a signal with a sinusoidal
wave. In accordance with
the power supply, temperature and noise frequency stability is comparatively
far better for these oscillators. Its disadvantage is that it cannot be
implemented easily on a monolithic IC(a monolithic ic is
an electronic circuit built on a single semiconductor base material or a single
chip ).

 

2.    Relaxation
oscillators: here the output signal is in a triangular form and offers a wide
range of operational frequencies. They
can easily be implemented on monolithic ICs, which can be tunable over a wide
range of frequencies.

 

3.     

APPLICATIONS OF VOC:

1. Electronic jamming equipment.

2. Function generator.

3. Production of electronic music, for production
of different types of noise.

     4. Phase
locked loop.

5. Frequency synthesizers, used in communication
circuits.

6. Tone Generators

7. Clock generators

8. Frequency Shift Keying

   9. In synthesizers to generate variable
tones for the production of electronic music.

 

PARAMETERS:

1.   
High-temperature stability
is desirable, meaning, the voc must be
able to operate stably and efficiently under high temperatures.

2.   
In general, operating temperature must be adequate.
Extreme working temperatures will lead to technical problems.

3.   
The frequency must be controllable by means of
other parameters like current, voltage,
etc.

4.   
Low power consumption is desirable. Low power
consumption will make the amplifier more efficient and more economic.

5.   
High frequency is a parameter to look out for,
because high frequency means better performance.

6.   
It must have a wide tuning range. Having a wide
tuning range makes the amplifier generally more and widely useful.

7.   
It must have
low noise. Noise is an undesirable signal, so the lesser the noise, the better
the amplifier.