Wien Bridge Oscillator

 

• The function of the Wien bridge oscillator is to generator sinusoidal frequency. 
• It is audio frequency oscillator.

Circuit Connection Diagram

• The Wien bridge circuit is connected between amplifier input and output terminal. 

Inductor & Inductance

 

• If several number of turns are wound over the core, it is generally called as Inductor. 

• There are no power loss in the pure inductor. 
• The core of magnetic material has negligible loop area is used in order to make inductor. 

Band Reject Filter OR Band Elimination Filter

 

Band Reject Filter ( Band Elimination Filter ) ( Band Stop Filter )

• It is a filter in which frequencies below lower cut off frequencies and above higher cut off frequencies are passes whereas stop band frequencies are attenuated.

Range of frequencies
f < fL	fL < f < fH	f > fH
Allowed to pass	Not allowed to pass	Allowed to pass

 

Band Pass Filter

• The band pass filter allows frequencies to be passed between lower cut off frequency ( f_L ) and higher cut off frequency ( f_H ) whereas it reject all other frequencies below f_L and above f_H.

Where

f_L = Lower cut off frequency

f_H = Higher cut off frequency

High Pass Butterworth Filter

 First order High Pass Butterworth Filter

• The high pass filter is obtained by changing frequency determining component – resistors and capacitors in the low pass filter. 
• The first order high pass filter is obtained by interchanging R and C in the first order low pass filter. 
• Figure shows first order high pass Butterworth filter.

Low Pass Butterworth Filter

 

First order Low Pass Butterworth Filter

• It is a filter which has nearly ideal response, flat passband as well as flat stop band. 
• As both passband and stop band are flat, it is also called as flat – flat filter.

Types of Filter

 Filter

• An electronics filter is a circuit which allows specific band of frequencies whereas blocks frequencies outside of the band.

Classification of Filter

1	Active
2	Passive