Find the variations in current and voltage gains and also the input admittance of the amplifier circuit shown in Fig. ex.8.3 with frequency. The Ebers-Moll model of the transistor BCY70 is available as the prime model.

Question

Accepted Answer

AUDIO AMPLIFIER. BASAK.
Rl 1273 0 2 ;
R2 2.573 2 0 ;
R3 73 0 4 ;
R4 510 3 0 ;
Cl 0.01 7-6 1 2 ;
C2 1007-6 3 0 ;
DB1 PNP 'MULLARD® ' BCY70@ 4.5 1 7-3 NODES 3 2 4;

[latex]V_{CE} I_{C}[/latex]

PORTS 10 4 0; ← Input Output
OUTPUT(IG2, YI1, VG2) ; ports ports
STEP LOG 100 10?4 5 ;

[latex]\uparrow \uparrow \uparrow[/latex]

REPEAT ; Hz
END ; Start Step Step

FREQUENCY	INPUT	ADMITTANCE	VOLTAGE		CURRENT
	PARALLEL	FORM	GAIN		GAIN
			I/P-O/P		I/P-O/P
HZ	REAL	IMAG	MOD	PHASE	DB	PHASE
100.000	6.582?-08	6.275?-06	.3327	293.6	-65.51	24.16
158.489	1.605?-07	9.943?-06	.5604	285.0	-64.98	15.93
251.189	3.974?-07	1.575?-05	.9118	278.8	-64.75	10.22
398.107	9.911?-07	2.494?-05	1.460	274.6	-64.66	6.468
630.957	2.477?-06	3.943?-05	2.322	270.4	-64.62	4.040
1000.00	6.178?-06	6.212?-05	3.675	266.8	-64.60	2.467
1584.89	1.528?-05	9.698?-05	5.784	262.5	-64.60	1.421
2511.89	3.695?-05	1.482?-04	8.999	256.7	-64.59	.6817
3981.07	8.495?-05	2.154?-04	13.65	248.6	-64.59	.0890
6309.57	1.759?-04	2.831?-04	19.64	237.7	-64.59	359.5
10000.0	3.068?-04	3.156?-04	25.94	224.7	-64.59	358.8
15848.9	4.358?-04	2.925?-04	30.91	211.8	-64.60	357.9
25118.9	5.235?-04	2.399?-04	33.88	201.2	-64.61	356.5
39810.7	5.693?-04	1.960?-04	35.32	193.4	-64.63	354.4
63095.7	5.905?-04	1.797?-04	35.94	188.1	-64.70	351.1
100000	6.009?-04	1.980?-04	36.20	184.3	-64.85	346.1

END

Note: Here small signal analysis has been used to obtain the frequency response together with the input admittances.

Question 8.3: Find the variations in current and voltage gains and also th...

Related Answered Questions

Develop a macromodel for the operational amplifier LM118 using the data given in Table ex.8.4. ...

Verified Answer:

In order to determine the d.c. conditions of the circuit of Fig. ex.8.5(a) obtain a set of general equations in matrix form which can be solved using the Newton-Raphson algorithm. Compute the d.c. voltages at the nodes of the circuit if the transistor is in forward active region. The saturation ...

Verified Answer:

Plot and dimension the output waveform for the circuit shown in Fig. ex.8.2(a). The input is a symmetrical triangular waveform of ±0.3 V magnitude having a frequency of 1 kHz. Given VBE(ON) = 0.2 V and βF = 100. ...

Verified Answer:

Verified Answer: