check my spec sheets?! you can't make me, you're not my dad! :-D it's hard to quiet my head down. thinking of how to use the 3.3v GPIO on my ESP3622 on a PNP transistor to source from 24v through a motor has been making my head go quiet. i've been googling and reading for a week, and your diagram at 8:44 finally makes sense to me. now my brain is alive with such high quality thoughts as, "mustachioed yachtsman" and "balloon laundry" ah, that's way more clear. back to normal! :-P thank you so much!
Excellent tutorial. I'm going to have to watch this several times. I'm trying to get a triple half bridge transistor circuit working so I can test a sensorless bldc motor driver I'm working on.
Links: Using the ULN2003A Transistor Array with Arduino Using the ULN2003A Transistor Array with Arduino www.bristolwatch.com/ele/uln2003a.htm ULN2003A Darlington Transistor Array with Circuit Examples ----- Using the TIP120 & TIP120 Darlington Transistors with Arduino Using the TIP120 & TIP120 Darlington Transistors with Arduino www.bristolwatch.com/ele/tr3.htm Tutorial Using TIP120 and TIP125 Power Darlington Transistors ----- Using Power MOSFETS with Arduino Using Power MOSFETS with Arduino www.bristolwatch.com/ele/tr2.htm N-Channel Power MOSFET Switching Tutorial www.bristolwatch.com/ele/tr1.htm P-Channel Power MOSFET Switch Tutorial ----- Using PNP Bipolar Transistors with Arduino, PIC Using PNP Bipolar Transistors with Arduino, PIC Using NPN Biploar Transistors with Arduino, PIC Using NPN Biploar Transistors with Arduino, PIC www.bristolwatch.com/ele/tr4.htm Understanding Bipolar Transistor Switches ----- How to build a Transistor H-Bridge for Arduino, PIC How to build a Transistor H-Bridge for Arduino, PIC www.bristolwatch.com/ele/tr5.htm Build a High Power Transistor H-Bridge Motor Control www.bristolwatch.com/ele/tr6.htm Driving 2N3055-MJ2955 Power Transistors with Darlington Transistors ----- Build a Power MOSFET H-Bridge for Arduino, PIC Build a Power MOSFET H-Bridge for Arduino, PIC www.bristolwatch.com/ele/h_bridge.htm H-Bridge Motor Control with Power MOSFETS www.bristolwatch.com/ele/tr7.htm More Power MOSFET H-Bridge Circuit Examples
Hi Lewis, today I just searched for some Raspberry infos. Now I stuck on your videos on RU-vid over hours. Great work!! Just one hint: In "More Power MOSFET H-Bridge Circuit Examples" Figure 4 ( Figure 4 ) is missing...
Thanks for these video series. I'm realy new to electronic and I still have some problems with the basics of transistors. Each time I do the math, half the time I'm wrong and I not always understand why. As example, in the "PNP Darlington Transistor with NEG common", I do the math as here under : R1=10.3/(5A/1000) = 2060 Ohms (so we choose a smaller value 2K) R2=4.4/(5mA/100) = 88000 Ohms and here I don't understand why you choose 2.2K that is far from the calculated value. Is it a mistake or is there a common explanation that I do not know ? Thanks for your help ;)
Thank you. Conventional current is making it very difficult to learn this subject . Been trying to teach myself for a long time and its caused a lot of confusion. They say it makes no difference but i find that it does, especially with semiconductors. So its good to be shown whats really going on in a circuit for a change.
OK, probably a dumb question and maybe I missed something along the way, but WHY would I want to use both a PNP and an NPN transistor to drive a motor? I could do the same thing with two NPN transistors and achieve the same level of amplification, right? The only difference that I see is that the motor is connected on the low side as opposed to the high side which would otherwise be the case if using a pair of NPNs. So the only reason I can think of doing it this way would be to protect from a possible short to ground on the motor.
Right, I understand the polarity is inverted, but my question is for the example in this video. Is there any real advantage to using a PNP over an NPN design just to turn a motor on and off? Maybe this was just an example to show how to design a PNP circuit. If so, that's fine, I just want to know why someone would want to design this circuit using PNP over NPN in this particular case. Maybe you want to interface this to an existing circuit and the polarity matches when using PNP. Other than that, and the reason I gave previously, are there any compelling reasons to use PNP over NPN specifically for the above example?
@@Enigma758 Automotive use for example, if you need to drive a motor with chassis attached to chassis ground, witn PNP you only send the colector signal to + of the motor...for led stripp with common ground...and so on...
OMG.. negative electrons moving, the only way to think...:) love these videos. i have a LC-V2F with a LM331 chip, no schematic OC-OUT is NPN common cathode, this will help. thanks a lot...:)
It's a very good explanation of how the transistors are working, I really liked it! One question: in the example beginning from 8:20, when the 5V is coming from the arduino, why should we substract 0.6 volts from that 5? Thank you!
I have a question. Is the device being powered supposed to share ground with arduino? I have circuit similar to the one at 8:52 and it's not working even when i skip NPN and bridge PNP with board's ground altogether.
Unless you use opto-couplers for isolation that involves a little more circuitry then yes. The emitter of Q2 and the motor negative share grounds with Arduino.
@@LewisLoflin Is it safe for the board? My device in place of motor is also 12v and board being used is esp8266 with 3.3V on IO. Power supply is 5v USB. Does the voltage difference with shared ground matter?
The 3A in the Ic of Q3 is the required motor current or Imotor. If Q3 hfe (DC gain) is 20 then the current I need for Ib is Ic / hFE = 3A / 20 = 0.15A or 150mA. Ic is Imotor.
The one that you control the PNP transistor with Arduino by using a npn and a pnp and applying a high to the npn which switches the pnp. I haven't tried it yet, but I believe we need a pull up on the pnp and pull down on npn so that it doesn't float and turn on by itself. Maybe a resistance value of 10 times the R value on the bases? Thanks! Great videos!
JPEE2009 You don't need a pull up - when the NPN driving the PNP is switched on a current path from emitter to base on the PNP switches it on. See the following link:www.bristolwatch.com/ele/tr4.htm
Hi, my answer is almost the same, but I want to know if is possible change the NPN transistor for two pull down resistor and put the arduino output 5v between them...
First of all, great videos. I really enjoyed your videos. But what bothers me, is that you insist that the current flows from negative to positive. Although that this is true, electrons flow from negative to positive. All the symbols and terminology is based on the current flow from positive to negative. ie. Sink as in go downwards to ground, source as in flow outwards of positive. If you would teach this "wrong" it would be easier to understand the current flows as in a transistors the arrows would point in the right direction.
The problem is that I teach electronics and electricity the problem being is semiconductors don't operate alone. Then what do you do with a positive ground? Many early semiconductor radios, etc. had positive grounds. The arrow in fact points to the negative semiconductor material. But you comment is well noted. Thanks.
Yes, I agree with that. There's a reason is called conventional current flow, because by convention it was agreed upon to treat it that way. But every once in a while there comes people that insist to use the real current flow, I think they think that makes it more interesting... not sure. But it does make it harder for people that just want to learn the basics.
Hi Lewis, as well as an excellent electronics video blog, I am totally fascinated by your articles/blogs on Christianity and Christian theology. As a Muslim, we always believed that Jesus was a Jew, was born a Jew- from a mother of Jewish descent. In his life time Jesus did not hear of the term "Christians or Christianity" and in fact its was Paul (known as Saul) who instigated and propagated the idea of Christianity.
Electron flow is correct. But today I use conventional because of what is taught today. See the following on this issue: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-BhHTRMGXO7Q.html MOSFETs and electron flow.
Conventional current is positive to negative (flow of holes). Actual electron flow is negative to positive. You just have to specify which usage you are using. The terms "sink" and "source" presume the conventional usage, and that is why they don't fit the electron flow usage in your example. The confusion in your videos is solely due to the ambiguity of your use. Both are correct.
@@LewisLoflin I know where you're coming from, but I think it's more a question of clearly communicating by explicitly stating which model you are using in any given statement. If you are getting this all the time, that might tell you something.
