Transistor common emitter amplifier

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Resistanceisfutile

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Hi
So I've got a transistor and a datasheet for it.
I've found many values including those for; Ic, Vceo, Vcbo, Vebo, Ibl (base cutoff current), Icex (collector cutoff current), Collector-emitter saturation voltage and Base-emitter saturation voltage.
I was just wondering, how would I use this information to help me build a common-emitter amplifier?
 

hi,
Its usual to have an application in mind when starting to design a BJT amplifier.
eg: DC or AC amp, output power , frequency range [ bandwidth], impedances etc.

What application are you considering.?
E
 

Currently just audio, so no higher frequency than 20 KHz. I was thinking of trying the voltage divider biasing technique, I just wondered if there's some equations (relevant to the stats I found for my transistor) I use to select the components?
 

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1) Pick a certain supply voltage and idling collector current. Then the collector resistor and emitter resistor values can be calculated.
2) Check the datasheet of the transistor for its minimum hFE at the collector current you have selected.
3) Calculate a base current from the minimum hFE then use 10 times as much current in the voltage divider and calculate their values.
4) Add a bypass capacitor parallel to the emitter resistor for maximum voltage gain, maximum distortion, minimum bandwidth and minimum input impedance.
5) Pick the minimum frequency (7Hz?) then calculate the values for the input capacitor, output capacitor and emitter capacitor.
 

    V

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