How to choose Hfe in common emmiter amplifier circuit

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When constructing a common emitter amplifier circuit using the BC107bp transistor, it's essential to choose the appropriate Hfe value based on the collector current. For a collector current of 1mA, selecting an Hfe of 200 is advisable, as it provides a balance between performance and stability. The choice of Hfe can significantly impact the amplifier's frequency response and input impedance, depending on the configuration used. Conducting a worst-case analysis is recommended for design engineering, while beginners should start with average values and explore parameter extremes for educational purposes. Understanding these variations is crucial for effective circuit design.
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I am using a transister model BC107bp in multisim, and i found that its min Hfe is 40 and max Hfe is 450. If I want to construct an amplifier circuit, i should choose the min or average? I found most of the datasheet show the hfe of collector current at 2m A (min 200 - max 450), but if my collector current is 1mA, should i choose the min Hfe which is 40? Any suggestion?
 
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It depends on the amplifier configuration.
If it is a common emitter amplifier then high frequency response will be hurt by a high Hfe.
If it is a common base amp it will not be sensitive to Hfe variation.
If it is common collector, (emitter follower), then input impedance will be affected by Hfe variation.

Design engineering requires that you perform a worst case analysis where all parameters vary. A student or hobbyist should start modelling with average values, then test some parameter extremes as a learning exercise. Explaining the changes observed with parameter changes will be highly educational.
 
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For the Ic = 1mA you shoudl choose hfe = 200.
 

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