MHT CET · Physics · Semiconductors
A transistor has a voltage gain 'A'. If the amount ' \(\beta A^{\prime}\) of its output is appl put of the transistor, then the transistor becomes oscillator where
- A \(\beta=0\)
- B \(\beta \mathrm{A}=1\)
- C \(\beta A=\infty\)
- D \(\beta A=0\)
Answer & Solution
Correct Answer
(B) \(\beta \mathrm{A}=1\)
Step-by-step Solution
Detailed explanation
The voltage gain of oscillator circuit is given by \(A_{f}=\frac{A}{1-A \beta}\)
where, \(\mathrm{A}\) is the voltage gain without feedback and \(\mathrm{p}\) is called feedback factor.
For sustained oscillation, from Barkhausen criterion
\(A \beta=1\)
where, \(\mathrm{A}\) is the voltage gain without feedback and \(\mathrm{p}\) is called feedback factor.
For sustained oscillation, from Barkhausen criterion
\(A \beta=1\)
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