Principles of Analog Electronics

Principles of Analog Electronics

386

Our rst C.E. conguration is illustrated in Figure 11.17.

We have a DC source

V

CC

that biases the transistor to work in its active region, a

sinusoidal voltage source

v

s

for input, a load resistor

R

L

for output, and the BJT is

a silicon npn-type with output characteristic curves as represented in Figure 11.18.

To operate in class A conditions (Section 10.2.4 in Chapter 10), we require a

Q-pointapproximately in the middle of the active region.

Amplier's

FIGURE 11.16 Analysis to perform the study of an amplier.

I

B

= 125 μ

A

150 μA

175 μA

200 μA

225 μA

30

20

10

0

0510 15 20

V

CE

[V ]

I

C

[mA]

FIGURE 11.18 Output character