- #1
linear_shift
- 16
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Hi,
In a common emitter amplifier circuit, I am considering the base-emitter junction. When you apply a base current, you get the base-emitter resistance, according to thermal_voltage/base_current. But when you get that resistance and place it in it's position in series with the emitter resistor in the amplifier circuit, it changes the base current. What gives? What keeps it at the same value (for given thermal voltage, beta/Hfe, etc)? Certainly I'm missing something here (probably something elemental ;D ). I know base-emitter resistance isn't supposed to matter much in a typical common emitter amp, but this question has been bugging me for some time now. :P
Thanks,
LS
In a common emitter amplifier circuit, I am considering the base-emitter junction. When you apply a base current, you get the base-emitter resistance, according to thermal_voltage/base_current. But when you get that resistance and place it in it's position in series with the emitter resistor in the amplifier circuit, it changes the base current. What gives? What keeps it at the same value (for given thermal voltage, beta/Hfe, etc)? Certainly I'm missing something here (probably something elemental ;D ). I know base-emitter resistance isn't supposed to matter much in a typical common emitter amp, but this question has been bugging me for some time now. :P
Thanks,
LS