Question

A collector feedback circuit uses an npn transistor with Vcc= 12V, Rc= 1.2V, RB = 47KΩ. Determine the collector voltage and the collector current if ß = 200.

Answer 1

Since the circuit voltage is equal to the sum of the drop voltage and the collector voltage, $V_c=V_{cc}-R_c$ , where $V_c$ is the collector voltage, therefore

$V_c=12-1,2=10.8$ V, since the current voltage falls to the base, therefore, according to the law of Oma $I_b=\frac {R_c}{R_b}$ , and since $I_c=I_b\times β$ ; $I_c=\frac {R_c}{R_b} \times β =\frac {1,2}{47\times10^3} \times 200 \approx 0.051$ A.