Hello, I meant to ask if I were to use a hall sensor such as A3144 as a switch to the gate of an NPN mosfet, would I need to connect its output pin using a 1K resistor directly to the gate of the mosfet like you have it or should be routed differently. It seems that the hall's output maybe directly connected to the gate without a resistor and then the resistor is used to connect its output directly to positive side of the circuit. Is this the case or how does that work? You can see it below at 1:27 into the video. I am just a little confused with it. It looks to me that if you removed his hall completely the gate is still getting power from the positive terminal bypassing the hall. It sure looks obvious. I am not even sure if his circuit makes sense. He surely uses up to 24 volts or so to feed his circuit. And what happens to the back emf of his coil when the hall is off? I like to build his circuit but I am just not clear. Something is not right. I have tried it and something is wrong. I like to do it right. I notice you don't have any video energizing a coil as a load on the transistor side. Another issue I have in mind is for the above transistor to be used as a switch doesn't the gate and the drain have to get shorted circuited to reset it every time ( meaning it has to be turned off) before you can turn it on again. To my knowledge that is how you turn it off otherwise it seem to remain in on position at least for sometime. I have checked this using my ohmmeter. So how does it get shorted in a circuit such as the one I mentioned. Thanks in advance ruclips.net/video/WjEJ7FFgbuI/видео.html
I am not sure, but for the PNP case, I think either the resistor or the LED (or load), or both, need to be put between the Collector and -V. An admittedly brief query via The Google yielded no example circuits with a PNP Collector connected *directly* to ground; there is always at least a resistor. Do you know if the circuit as diagrammed will work? I suppose if there was a voltage drop from Base to Collector then it might work, although the voltage drop would be small and that would affect the choice of resistor. If it would not work then it is unfortunate, as your diagram that moves only the switch shows a symmetry that makes the concept expressed very clear.
Thank you. I Have been struggling to make this circuit work from his book and I have been baffled. It would only work if I disconnected the collector that was running straight to the Neg terminal. I made your adjustment and it works!!!!
Thank you, really cleared up some things. my school got us to do this circuit. thing is i dont think they know there are 2 types of transistors. They have used a pnp transistor on a npn transistor 'socket'.
R1 is there to protect the LED so needs to be in the region of 470 ohms. You could go a bit smaller, but if you go too small, you run the risk of burning out the LED. R2 is ther to reduce the current to the base of the transmitter. You could use a much bigger resistor here if you wanted too, say, 10k. If you go too big, there won't be enough current to switch on the transistor. You could go smaller as well because the base of the transmitter can cope with quite a large current range.
Change biased voltage or variable ressistor or change PNP to npn or vice versa or ultrasound reset electrical routing...that is why it cost a bank to run big business maintenance cost
The gate of NPN going to positive and the PNP goes to the negative terminal. So what you are actually perhaps meaning to say and not saying is that the game is that they have simply decided to swap the names of the emitter and the collector while in real actual transistor their respective locations are exactly in the same place. In other words the middle pin of each transistor by whatever names is called goes to positive and the right hand pin goes to negative aside from labels. Also another anomaly is that in the actual picture of the two transistor the gate is the left pin while in circuits it is the middle part in the transistor symbol. Is what I have said actually true?
So is the NPN called forward bias because of a positive charge going through the base to the emitter. And a PNP a reverse bias because positive charge comes in through the emitter and leaves through the base. ??? Thank you. 👍🍻
Hi Carlos. It's interesting that you say that because I am just in the process of buying a new microphone to make the narration clearer on new videos. I hope that the sound was not too annoying for you. Thanks for watching the video and taking the time to comment. Much appreciated, John
CONGRATULATIONS; IS THE BEST EXPLANATION TO DIFFERENT CURRENTS FLOW IN PNP-NPN TRANSISTORS.
Hello,
I meant to ask if I were to use a hall sensor such as A3144 as a switch to the gate of an NPN mosfet, would I need to connect its output pin using a 1K resistor directly to the gate of the mosfet like you have it or should be routed differently.
It seems that the hall's output maybe directly connected to the gate without a resistor and then the resistor is used to connect its output directly to positive side of the circuit. Is this the case or how does that work?
You can see it below at 1:27 into the video. I am just a little confused with it. It looks to me that if you removed his hall completely the gate is still getting power from the positive terminal bypassing the hall. It sure looks obvious. I am not even sure if his circuit makes sense. He surely uses up to 24 volts or so to feed his circuit. And what happens to the back emf of his coil when the hall is off? I like to build his circuit but I am just not clear. Something is not right. I have tried it and something is wrong. I like to do it right. I notice you don't have any video energizing a coil as a load on the transistor side.
Another issue I have in mind is for the above transistor to be used as a switch doesn't the gate and the drain have to get shorted circuited to reset it every time ( meaning it has to be turned off) before you can turn it on again. To my knowledge that is how you turn it off otherwise it seem to remain in on position at least for sometime. I have checked this using my ohmmeter. So how does it get shorted in a circuit such as the one I mentioned.
Thanks in advance
ruclips.net/video/WjEJ7FFgbuI/видео.html
Short simple straight to the point....Excellent
Great - thanks very much for your positive feedback
I am not sure, but for the PNP case, I think either the resistor or the LED (or load), or both, need to be put between the Collector and -V. An admittedly brief query via The Google yielded no example circuits with a PNP Collector connected *directly* to ground; there is always at least a resistor. Do you know if the circuit as diagrammed will work? I suppose if there was a voltage drop from Base to Collector then it might work, although the voltage drop would be small and that would affect the choice of resistor.
If it would not work then it is unfortunate, as your diagram that moves only the switch shows a symmetry that makes the concept expressed very clear.
Thank you. I Have been struggling to make this circuit work from his book and I have been baffled. It would only work if I disconnected the collector that was running straight to the Neg terminal. I made your adjustment and it works!!!!
Brilliant! Clear and concise.
Thank you, really cleared up some things. my school got us to do this circuit. thing is i dont think they know there are 2 types of transistors. They have used a pnp transistor on a npn transistor 'socket'.
I'm glad you found the video useful. Thanks for commenting on it. Cheers, John
thanks sir but what about signal amplifing ? can we do apply the same trick?
cheers
Why isnt the collector of the npn hooked up to the negative as it is an npn transistor
Nice...quite informative...thanks...
You're welcome Harry. Thanks for watching the video and commenting. Cheers, John
Why is one resistor larger than the other?
R1 is there to protect the LED so needs to be in the region of 470 ohms. You could go a bit smaller, but if you go too small, you run the risk of burning out the LED. R2 is ther to reduce the current to the base of the transmitter. You could use a much bigger resistor here if you wanted too, say, 10k. If you go too big, there won't be enough current to switch on the transistor. You could go smaller as well because the base of the transmitter can cope with quite a large current range.
Thanks!
Change biased voltage or variable ressistor or change PNP to npn or vice versa or ultrasound reset electrical routing...that is why it cost a bank to run big business maintenance cost
Good
The gate of NPN going to positive and the PNP goes to the negative terminal. So what you are actually perhaps meaning to say and not saying is that the game is that they have simply decided to swap the names of the emitter and the collector while in real actual transistor their respective locations are exactly in the same place. In other words the middle pin of each transistor by whatever names is called goes to positive and the right hand pin goes to negative aside from labels.
Also another anomaly is that in the actual picture of the two transistor the gate is the left pin while in circuits it is the middle part in the transistor symbol.
Is what I have said actually true?
Thanks for your feedback - useful comments 👍
So is the NPN called forward bias because of a positive charge going through the base to the emitter. And a PNP a reverse bias because positive charge comes in through the emitter and leaves through the base. ??? Thank you. 👍🍻
nice
Please louder.
Hi Carlos. It's interesting that you say that because I am just in the process of buying a new microphone to make the narration clearer on new videos. I hope that the sound was not too annoying for you. Thanks for watching the video and taking the time to comment. Much appreciated, John
Your voice is week
7days?