About halfway through the video I was getting ready to write a comment saying, "No, you're wrong, it's not negative resistance, it's just a consequence of saturation." I'm glad you came around to my point of view. Obviously, we must be right since great minds think alike. 🤓 There's one small point where I still disagree. I think you said that in saturation there's a 0.4 V drop from collector to emitter. But I think the 0.4 V drop is actually across the (forward-biased) base-collector diode. That's how I've always seen it in Ebers-Moll models in textbooks. That means the rising base voltage directly causes the collector voltage to rise, rather than indirectly through the emitter current. Thanks for another excellent video!
I really was analyzing this in real-time. I had never thought much about the cause of the bump until someone asked me to explain it. I hope this showed how mastering the fundamentals helps to understand more complex circuits.
At 11:40 he says that when saturated (fully on) the transistor will have 0.4V between the collector and emitter. This is wrong. It will be a few tens of millivolts.
Good day! Regarding loss compensation (using negative resistance) in a microwave filter, how could I design a common emitter RF amplifier with input impedance (seen looking into the base terminal) that has a -R and capacitive reactance? I've been trying to implement this through a Colpitts oscillator design method, but don't want the circuit to oscillate. Since two conditions are required for oscillation, could it be as simple as making sure at least one condition isn't met, or do I have to move (in design) above or below those conditions?
About halfway through the video I was getting ready to write a comment saying, "No, you're wrong, it's not negative resistance, it's just a consequence of saturation." I'm glad you came around to my point of view. Obviously, we must be right since great minds think alike. 🤓
There's one small point where I still disagree. I think you said that in saturation there's a 0.4 V drop from collector to emitter. But I think the 0.4 V drop is actually across the (forward-biased) base-collector diode. That's how I've always seen it in Ebers-Moll models in textbooks. That means the rising base voltage directly causes the collector voltage to rise, rather than indirectly through the emitter current.
Thanks for another excellent video!
I really was analyzing this in real-time. I had never thought much about the cause of the bump until someone asked me to explain it. I hope this showed how mastering the fundamentals helps to understand more complex circuits.
If I understand you correctly, you're saying the rising base current "re-reverses" (forward biases) the base-collector junction of the transistor?
At 11:40 he says that when saturated (fully on) the transistor will have 0.4V between the collector and emitter.
This is wrong. It will be a few tens of millivolts.
Thank u sir for sharing godbless😊
Negative resistance? George Ohm must be spinning in his grave!
Good day!
Regarding loss compensation (using negative resistance) in a microwave filter, how could I design a common emitter RF amplifier with input impedance (seen looking into the base terminal) that has a -R and capacitive reactance? I've been trying to implement this through a Colpitts oscillator design method, but don't want the circuit to oscillate.
Since two conditions are required for oscillation, could it be as simple as making sure at least one condition isn't met, or do I have to move (in design) above or below those conditions?
Stupid me watched this to find out about negative resistance!
That's litterally the worst name for a phenomenon ever, it's more like S curve resistance.
nuh uh