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I need to know if my formula's are correct for current gain. Sorry for shakey drawing.

I know beta would change the dc values slightly but for my prof. it's close enough.

Beta AC = 70.

VB = R1R2/R1+R2

VE = VB - VBE

IE = VE/RE

r'e = 25mv/IE

Req = R1 || R2

Rout = RC || RL

Av = Rout/ r'e

Vout = Av * Vin

Ai = Iout/Iin

Iin= Vin/Rin(total)

Rin(total) = Req || Beta AC(Rin(base))

Rin(base) = Beta AC * r'e

Iout = Ic + Il

Il = Vout/ RL

Bolded is what I am unsure off.

I know current out is the combination of current through the collector resistor and the load resistor since AC see's DC source as a ground. So, does that mean the current in multiplied by beta is equal to the current through the collector?

I know beta would change the dc values slightly but for my prof. it's close enough.

Beta AC = 70.

__DC Analysis__VB = R1R2/R1+R2

VE = VB - VBE

IE = VE/RE

__AC Analysis__r'e = 25mv/IE

Req = R1 || R2

Rout = RC || RL

__Voltage Gain__Av = Rout/ r'e

Vout = Av * Vin

__Current Gain__Ai = Iout/Iin

Iin= Vin/Rin(total)

Rin(total) = Req || Beta AC(Rin(base))

Rin(base) = Beta AC * r'e

Iout = Ic + Il

**Ic = Beta AC * Iin**Il = Vout/ RL

Bolded is what I am unsure off.

I know current out is the combination of current through the collector resistor and the load resistor since AC see's DC source as a ground. So, does that mean the current in multiplied by beta is equal to the current through the collector?

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