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प्रश्न
The amplifiers X, Y and Z are connected in series. If the voltage gains of X, Y and Z are 10, 20 and 30, respectively and the input signal is 1 mV peak value, then what is the output signal voltage (peak value)
- if dc supply voltage is 10V?
- if dc supply voltage is 5V?
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उत्तर
Total voltage amplification is defined as the ratio of output signal voltage and input signal voltage.
According to the problem. voltage gain in X, vx = 10
Voltage gain in Y, vy = 20
Voltage gain in Z, vz = 30
ΔV1 = 1 mV = 10–3 V
And Total voltage amplification = vx × vy × vz
ΔV0 = vx × vy × vz × ΔV1
= 10 × 20 × 30 ×10–3 = 6V
- If DC supply voltage is 10 V, then output is 6 V, since the theoretical gain is equal to practical gain, i.e., the output can never be greater than 6 V.
- If DC supply voltage is 5 V, i.e., Vcc = 5 V. Then, the output peak will not exceed 5 V. Hence V0 = 5 V.
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