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Question 13.1: Determining β from the Characteristic Curves Verify that the...

Determining β from the Characteristic Curves
Verify that the value of β is 100 for the transistor with the characteristics shown in Figure 13.5.

13.5
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The value of β can be found by taking the ratio of collector current to base current provided that vCE is high enough so that the collector base junction is reverse biased. For example, at vCE = 4V and iB = 30 μA, the output characteristics yield iC = 3 mA. Thus, the value β of is

\beta=\frac{i_C}{i_B}=\frac{3\mathrm{~mA}}{30~\mu\mathrm{A}}=100

(For most devices, slightly different values of β result from different points on the output characteristics.)

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