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प्रश्न
Draw a typical input and output characteristics of an n-p-n transistor in CE configuration. Show how these characteristics can be used to determine (a) the input resistance (r1), and (b) current amplification factor (β)
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उत्तर
CE configuration is the most widely used transistor.
Variation of base current (IB) with the base-emitter voltage VBE is called input characteristics.
Variation of collector current IC with the collector − Emitter voltage VCE is called output characteristics
Input characteristics
Output characteristics
Parameters of Transistors
Input resistance (ri)
`r_i = ((triangleV_"BE")/(triangleI_B))_(V_"CE")`
ΔVBE − Base-emitter voltage
ΔIB − Base current
VCE − Constant collector-emitter voltage
Output resistance (r0)
`r_0 = ((triangleV_"CE")/(triangleI_C))_(I_B)`
ΔVCE − Collector-emitter voltage
ΔIC − Collector current
IB − Base current
Current amplification factor (β)
`beta_(ac) = ((triangleI_c)/(triangleI_B))_(V_(CE))`
IC − Collector current
IB − Base current
VCE − Constant collector-emitter voltage.
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Figure 1
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Figure 2
