Recent content by 1rel

The true nature of the analog, real world always remains a secret to us, or hard to describe/imaging by us humans I guess. On the other hand, we can perfectly grasp the behavior of the basic elements of digital systems, because they are "symbolic devices", but we can only come up with...

Seeing the current as an unavoidable/necessary defect of the bipolar junction transistor is an interesting perspective! I often read that BJTs are current-controlled devices , and most of the books I've seen are stating it this way as well. Since I'm not able to understand them yet completely at...

This thread exploded, and I'm sorry, for the many questions about the basics without good foundations. - LvW and Jony130, thanks a lot for your great help, we've collected some useful examples on BJTs for beginners like me, that can be used by others too hopefully. The discussion about the BJT...

...for some reason I can't find the right keyword anymore, but a while ago I did some searching on some similar concept, and there's it seems to be some active research going on in this area right now. Some things that showed up right before: Body area networks...

What happens when the transistor goes into saturation mode? Or closer to saturation, i.e. IB increases, compared to IC? Let's say, in the 2nd configuration, top row from first post: RE = 100 Ω, RC = 1 kΩ, VCC = 5 V, β = 100. In our case, like Jony already showed, that is in saturation, and...

Probably, it will be difficult to make this very reliable/consistent, because you never know if the the foils really make a good contact for every hit. You could try to use an https://www.arduino.cc/en/Reference/AttachInterruptinstead of polling the pin (via ADC or digital), that might catch the...

That sounds like a nice project... Do you apply voltage (5 V) to one foil, and measure the voltage on the other via the ADC (analogRead())? What kind of foil do you use, and how are the separated, are they going to be replaced after every shot? It might also work by using a special arrow, or...

Right, I see! What really helped me recently, are those simulators that are showing the circuit behavior in realtime (in contrary to LTSpice). - They might be not that accurate (circuit - the open source one from the first post ( also circuitlab, everycircuit)). - It's great to be able to see...

Right, your graph shows emitter current VS base-emitter voltage, I wonder how it would look like for the base current. Similar to a diode I-V characteristic curve as well, right? Ah ok, I've seen that notation a couple of times, but wondered how it showed up in your example. Before I tried to...

(*Catching up, answering to previous posts here...*) Jony130: That was of great help understanding the initial example! Thanks a lot for the examples, those will come in handy in many situations! I was able to follow until the last example (RC = 10 kΩ). That's where I got stuck... That...

With my limited understanding of the subject, I would still agree. The base-emitter voltage VBE, i.e. the actual electrical field inside the transistor between those terminals, is the physical cause of the base current IB, that controls the collector current IC. A high enough voltage VBE...

Thank you for the help. This thread kind of blew up a bit, I'm sorry for that... too much info, too many questions. Right, the configuration on the right is indeed a common emitter and not a emitter follower anymore, because of that collector resistor. (Emitter degeneration was keyword I...

It was too much to get the two lower right circuits done on paper, so I played a bit with Sage, and it has a surprisingly nice equation solver in there! The output values differ quite a bit from the values in the simulation. But are they by any means realistic? That's the program used in sage...

Right, I'm taking that crude linear model, and replaced the collector-emitter path by this 0.2 V voltage source (just a constant drop of 0.2 V). However, this is all a bit abstract to me... So there are some conditions that say that the NPN BJT is in saturation mode... VCE <= 0.2 V (simplified...

Thank you for the patience :) Yes, I more or less see that, and also tried to play through an example with a resistor and a diode, and a 2 resistors in series. It works -- the crossing points show the actual current at a given voltage drop of over the part plotted in the circuit -- but I will...