Question 7.SP.8: Use SPICE methods to determine the voltage gain for the CG a......

Schaum’s Outline of Electronic Devices and Circuits [1089587]

Use SPICE methods to determine the voltage gain for the $CG$ amplifier of Example 7.3. Let $R_S = 2 kΩ$ and $v_i = 0.25 \sin(2π × 10^3 t) V$ for computational purposes.

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The netlist code that follows describes the circuit:

Prb7_8.CIR
vi 1 0 SIN(0V 0.25V 1kHz)
RS 1 0 2kohm
RD 2 0 1kohm
rds 1 2 30kohm
G 1 2 (1,0) 2e-3
.TRAN 1us 1ms
.PROBE
.END

Execute 〈Prb7_8.CIR〉 and use the Probe feature of PSpice to give the resulting waveforms for $v_i$ and $v_o$ shown by Fig. 7-15. The voltage gain is found as the ratio of the marked peak values.

A_{v} = {\frac{v_{i}}{v_{o}}} = {\frac{0.492}{0.250}} = 1.97

7.15

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