5.3 Amplifier Design Stages
209
A lower base current will determine a lower collector current and thereby act to correct the initial
increase in collector current. A dual argument applies if the collector current decreases. (video 5.1)
Figure 5.3-2 Voltage feedback bias network
The bias network shown in Figure 5.3-3 provides a further improvement since it may be
implemented with lower values of resistance and hence is more compatible with thin- or thick-film
resistor values which are often employed in radio frequency circuits.
Figure 5.3-3 Voltage feedback bias network which allows lower resistance values to be used
Active bias topologies are also an option and usually provide better bias stability, however
they are more expensive to realise.
C
E
B
CC
V
C
R
B
R
C
E
B
CC
V
C
R
1 B
R
B
R
2 B
R
Conquer Radio Frequency
209 www.cadence.com/go/awr
