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Question 3.7: For the transistor circuit of Fig. 3-8(a), R1 = 1 kΩ, R2 = 2......

For the transistor circuit of Fig. 3-8(a),  R_1 = 1  kΩ,  R_2 = 20  kΩ,  R_C = 3  kΩ,  R_E = 10  Ω, and V_{CC} = 15  \text{V}.    If the transistor is the generic npn transistor of Example 3.3, use SPICE methods to determine the quiescent values I_{BQ},  V_{BEQ},  I_{CQ}, and V_{CEQ}.

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The netlist code below models the circuit.

EX3_7.CIR – CE quiescent values
R1     0 1 1kohm
R2    2 1 20kohm
RC    2 3 3kohm
RE    4 0 10ohm
VCC  2 0 15V
Q 3 1 4 QNPNG
.MODEL QNPNG NPN(Is=10fA Ikf=150mA Isc=10fA Bf=150
+ Br=3 Rb=1ohm Rc=1ohm Va=30V Cjc=10pF Cje=15pF)
.DC VCC 15V 15V 1V
.PRINT DC IB(Q) IC(Q) V(1,4) V(3,4)

Execute 〈Ex3_7.CIR〉 and poll the output file to find

      VCC               IB(Q)             IC(Q)             V(1,4)             V(3,4)
1.500E+01      1.428E-05     2.575E-03     6.748E-01      7.252E+00

where I_{BQ} = IB(Q),  I_{CQ} = IC(Q),  V_{BEQ} = V(1, 4), and V_{CEQ} = V(3, 4).

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