Why CC amplifier is known as emitter follower?Īns: The common collector junction transistor amplifier is commonly called an emitter follower. The difference between higher cut off and lower cut off frequency is referred to as bandwidth ( f H- f L ).Ĭommon Collector Amplifier is studied and its Bandwidth is calculated.ġ. These are shown as f L and f H and are called as the 3dB frequencies are simply the lower and higher cut off frequencies respectively. In the usual application, mid band frequency range are defined as those frequencies at which the response has fallen to 3dB below the maximum gain (|A| max). Calculate the bandwidth from the graph.Plot the graph: gain (dB) verses Frequency on a semi log graph sheet.Keeping input voltage constant vary the frequency from 50 Hz to 1 MHz in regular steps and note down the corresponding output voltage.Set source voltage V s = 50mV (say) at 1 KHz frequency using the function generator.Connect the circuit as shown in the circuit diagram.Common collector state has a low output resistance, the circuit suitable to serve as buffer or isolating amplifier or couple to a load with large current demands. Since the output voltage across the emitter load can never exceed the input voltage to base as emitter-base junction would become back biased. In addition to that, the emitter follower increases the output level of the signal. This circuit performs the function of impedance transformation over a wide range of frequencies with voltage gain close to unity. In other words emitter follows the input signal. In common collector amplifier as the collector resistance is made to zero, the collector is at AC ground that is the reason for which the circuit is also called as grounded-collector amplifier or this configuration has voltage gain close to unity and hence a change in base voltage appears as an equal change across the load at the emitter, hence the name emitter follower is given to this circuit. To study the common collector amplifier and find it’s Bandwidth.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |