AdvancedA-002-003-004
What is the alpha of a bipolar transistor in common base configuration?
A
Answer
Circuit design and power supplies
Type
A
Forward current gain
B
Reverse current gain
C
Forward voltage gain
D
Reverse voltage gain
Answer Notes
In a bipolar junction transistor (BJT) wired in a common base configuration, "alpha" represents the forward current gain. It is defined as the ratio of the change in collector current to the change in emitter current.
Because the collector current is always slightly less than the emitter current (due to a small recombination current in the base), the alpha of a transistor is always just under 1.0 (typically 0.95 to 0.99). It measures current gain, not voltage gain, and specifically in the forward direction.
Previous · A-002-003-003
Which component conducts electricity from a negative emitter to a positive collector when its base voltage is made positive?
Next · A-002-003-005
In a bipolar transistor, the change of collector current with respect to base current is called: