I can't seem to find an answer to this question that is burning my brain...
In the Common-Emitter BJT amplifier circuit...the collector output voltage is inverted. That makes sense to me, sort of, as the base current increases the voltage between the emitter and collector decreases. But the current from emitter to collector *also* increases, right along with the base current...so why is the collector current not out of phase with the collector voltage 180 degrees?
I would expect the current from emitter to collector and emitter to base to be in phase with each other. And the voltage from emitter to collector to be 180 degress out of phase.
In fact, I'm thinking if you drop the amplifier out of this altogether and put two resistors in series, R1 + R2 with a fixed voltage source V1, and varied the resistance of R1, oscillating back and forth, you would also notice the current out of phase with the voltage *across R1*. As R1 increases, the voltage drop increases, and the current decreases (due to total circuit current decreasing), and as R1 decreases, the voltage drop decreases, and the current increases.
Am I wrong on this? Very confused...
In the Common-Emitter BJT amplifier circuit...the collector output voltage is inverted. That makes sense to me, sort of, as the base current increases the voltage between the emitter and collector decreases. But the current from emitter to collector *also* increases, right along with the base current...so why is the collector current not out of phase with the collector voltage 180 degrees?
I would expect the current from emitter to collector and emitter to base to be in phase with each other. And the voltage from emitter to collector to be 180 degress out of phase.
In fact, I'm thinking if you drop the amplifier out of this altogether and put two resistors in series, R1 + R2 with a fixed voltage source V1, and varied the resistance of R1, oscillating back and forth, you would also notice the current out of phase with the voltage *across R1*. As R1 increases, the voltage drop increases, and the current decreases (due to total circuit current decreasing), and as R1 decreases, the voltage drop decreases, and the current increases.
Am I wrong on this? Very confused...
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