For the fixed-bias configuration of Fig. 4.118 determine:
a.
b.
c.
d. VC.
e. VB.
f. VE.
FIG. 4.118
(a)
Write the expression of the base current \(I_{B Q}\).
$$ I_{B Q}=\frac{V_{C C}-V_{B E}}{R_{B}} $$
Substitute \(16 \mathrm{~V}\) for \(V_{C C}: 0.7 \mathrm{~V}\) for \(V_{B E}\) and \(510 \mathrm{k} \Omega\) for \(R_{B}\).
$$ \begin{aligned} I_{B Q} &=\frac{16 \mathrm{~V}-0.7 \mathrm{~V}}{510 \mathrm{k} \Omega} \\ &=30 \mu \mathrm{A} \end{aligned} $$
Hence the value of \(I_{B Q}\) is \(30 \mu \mathrm{A}\).
(b)
Write the expression of the collector current \(I_{C Q}\).
$$ I_{C Q}=\beta I_{B Q} $$
Substitute 120 for \(\beta\) and \(30 \mu \mathrm{A}\) for \(I_{B Q}\).
$$ \begin{aligned} I_{C Q} &=(120)\left(30 \times 10^{-6}\right) \\ &=3.6 \mathrm{~mA} \end{aligned} $$
Hence, the value of \(I_{C Q}\) is \(3.6 \mathrm{~mA}\).
(c)
Write the expression of the voltage \(V_{C E Q}\).
$$ V_{C E_{e}}=V_{C C}-I_{C Q} R_{C} $$
Substitute \(16 \mathrm{~V}\) for \(V_{C C}, 3.6 \mathrm{~mA}\) for \(I_{C Q}\) and \(1.8 \mathrm{k} \Omega\) for \(R_{C}\).
$$ \begin{aligned} V_{C E Q} &=16-\left(3.6 \times 10^{-3}\right)\left(1.8 \times 10^{3}\right) \\ &=16-6.48 \\ &=9.52 \mathrm{~V} \end{aligned} $$
Hence the value of \(V_{C E_{Q}}\) is \(9.52 \mathrm{~V}\).
(d)
Write the equation for the Voltage \(V_{C}\).
$$ V_{C}=V_{C E_{Q}} $$
Substitute \(9.52 \mathrm{~V}\) for \(V_{C E_{Q}}\).
$$ V_{C}=9.52 \mathrm{~V} $$
Hence the value of \(V_{C}\) is \(9.52 \mathrm{~V}\).
(e)
Write the equation for the Voltage \(V_{B}\).
$$ V_{B}=V_{B E} $$
Substitute \(0.7 \mathrm{~V}\) for \(V_{B E}\)
$$ V_{B}=0.7 \mathrm{~V} $$
Hence the value of \(V_{B}\) is \(0.7 \mathrm{~V}\).
(f) Since the emitter terminal of the transistor is connected to ground, the emitter voltage \(V_{E}\) is, \(V_{E}=0 \mathrm{~V}\)