Two amplifiers are connected one after the other in series (cascaded). The first amplifier has a voltage gain of 10 and the second has a voltage gain of 20. If the input signal is 0.01 volt, calculate the output ac signal.
Two amplifiers are connected one after the other in series (cascaded). The first amplifier has a voltage gain of 10 and the second has a voltage gain of 20. If the input signal is 0.01 volt, calculate the output ac signal.
Solution and Explanation
Voltage gain of the first amplifier, V1 = 10
Voltage gain of the second amplifier, V2 = 20
Input signal voltage, Vi = 0.01 V
Output AC signal voltage = Vo
The total voltage gain of a two-stage cascaded amplifier is given by the product of voltage gains of both the stages, i.e.,
\(V = V_1 × V_2 \)
\(V = 10 × 20 = 200 \)
We have the relation:
\(V = \frac{V_0}{V_i}\)
\(V_0 = V × V_i \)
\(V_0 = 200 × 0.01 \)
\(V0 = 2 V\)
Therefore, the output AC signal of the given amplifier is 2 V.
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Concepts Used:
P-n Junction
A P-N junction is an interface or a boundary between two semiconductor material types, namely the p-type and the n-type, inside a semiconductor.
Biasing conditions for the p-n Junction Diode:
in p-n junction diode two operating regions are there:
- P-type
- N-type
There are three biasing conditions for p-n junction diode are as follows:
- Zero bias: When there is no external voltage applied to the p-n junction diode.
- Forward bias: P-type is connected to positive terminal of the voltage potential while n-type is connected to the negative terminal.
- Reverse bias: P-type is connected to negative terminal of the voltage potential while n-type is connected to the positive terminal.