Question

The phase shift in common base amplifiers is

• A. ${180}^o$
• B. $0^o$
• C. ${90}^o$
• D. ${45}^o$

Answer 1

Answer: (B)

$0^o$

$Answer:-$ B

This transistor configuration provides a low input impedance while offering a high output impedance. Although the voltage is high, the current gain is low and the overall power gain is also low when compared to the other transistor configurations available. The other salient feature of this configuration is that the input and output are in phase.

If it is the normal audio frequency range, there is no phase shift between the input and the output. So, increasing current at the input gives rise to increasing output current . A decreasing input gives a decreasing output current. Hence, phase difference is zero.