Such a Great video. Perfect presentation. You showed us the problem. Discussed the theory. Simulated a solution. Then tested your solution.... Perfect video workflow.
@Dhiman.Sarkar3 жыл бұрын
Thanks. Nice explanation. This phenomenon has been bugging me for 4 days. Finally found the solution.
@willempje652 жыл бұрын
Thank you for enlightning us... I was fussing with BC547 / BC557, which were way to slow switching at 62.5kHz because of saturation... The (schottky) diode Base -> Collector was a gamechanger 🙂
@TYGAMatt9 ай бұрын
Fantastic. I was testing transistor switching speed today and it was very poor. Now I know how to speed things up. Thank you Sir
@p_mouse86764 жыл бұрын
Absolutely excellent video on the subject! 👍🏻 When you have to drive something like a mosfet, there is also something like a totem-pole circuit. Which can even switch faster as well as deliver a lot of current. Maybe it would be also interesting to see how these transistor circuits compare to switching with fets.
@BaconbuttywithCheese4 жыл бұрын
A very concise explanation of how and why without the math is refreshing and enlightening. Please do more like this.
@pepperjack84 жыл бұрын
Very good video. I am not sure who you work for, but I hope your employer value your talent.
@FesZElectronics4 жыл бұрын
I'm happy you enjoy my videos! Thank you!
@WalidIssa4 жыл бұрын
Great demonstration ....
@FesZElectronics4 жыл бұрын
Thank you! I'm happy you enjoyed it! To be honest I noticed this turn off issue when working with the SMPS drivers, they ended up switch very slowly, so I had to limit my switching frequency to
@gwc14104 жыл бұрын
Very useful video with a good demonstration. You make some very good videos.
@FesZElectronics4 жыл бұрын
Thank you very much!
@pieters2862 жыл бұрын
I just love this simulation hardware iterations to understand/improve the circuits. Thanks for sharing.
@JohnDuthie4 жыл бұрын
I'm new to all of this and I'm glad I found this channel!
@leofernekes343 Жыл бұрын
great video thank you!!!!
@homemade834 жыл бұрын
OMG. i have faced a very bad experiment with this circuit before and it was such a disaster in my project and after many search and modification on board i found it won't work even with the modifications you mentioned in this video , simply because my collector voltage was to be 24v and you have to maintain a certain collector current to get better switching times and of course there was much power dissipated in the pull-up resistor connected at the collector. after all that trouble i used another ic and it can handle my 4MHz with no problems at all also without any external components. i really wanted to thank you to share this video with us and warn others from this trick.
@SINHRO-FAZA23 күн бұрын
А если на выходе генератора к транзистору поставить керамический конденсатор, тем самым срезав большую постоянную перенасыщения при включении (для больших частот это не критично), тем самым тоже должно снизить высокое насыщение PN перехода внутренних обкладок. ?
@lorhancosta6224 жыл бұрын
Superb as always!
@ferdinandocostanzo757810 ай бұрын
Hi guys, when you download the model you need to ensure that string name inside is .SUBCKT BC817-25B 2 3 1 (like the video above) and not .SUBCKT BC817-25B 1 2 3 as in my case
@sharana.p59214 жыл бұрын
Thank you so much 😊. Please keep doing videos like this. One question, are you working for any company?
@andrewphillip84322 жыл бұрын
Great video, very helpful!
@SanjaySharma-pw6ww3 жыл бұрын
Thanks for the tutorial on switching delay of bjt.🙏👍
@reimundolopez11983 жыл бұрын
Can you do the same with a phototransistor? For example, the pc817. It is that they are also very slow for switching
@narasimha46604 жыл бұрын
Very useful information in very effective method.
@БогданМура Жыл бұрын
So BC549 that have 100MHz max, with this circuit can give 20MHh max?
@repeaterlanes8024 Жыл бұрын
If i may ask, how did you determine the necessary value for the speed-up capacitor? I cant seem to find anything about it.
@FesZElectronics Жыл бұрын
Depending on the frequency at which you want it to act, its impedance needs to be smaller than the resistor over which it is placed; if you have a capacitor placed over a 1k resistor, and you want to "speed-up" signals above 1MHz, you can determine the capacitors impedance Xc=1/(2*pi*F*C), so a 1nF capacitor will have 159R at 1MHz, it will have a considerable impact, but the same capacitor at 1KHz has 159Kohm, so it does nothing.
@0MoTheG2 жыл бұрын
Check out: 2N2369 and BSV52 they are true BJT switching transistors.
@styrishrodrigues2 ай бұрын
What symbol is in the video thumbnail?
@styrishrodrigues2 ай бұрын
It's shottky transistor
@ElukeNL9 ай бұрын
I guess the Schottky diode across BC also works without the split base resistor? Or is a combination of both these nescesairy? (Also: commenting for the algorithm)
@Electronzap4 жыл бұрын
That's very helpful :)
@DiegoColl444 жыл бұрын
Thank you for sharing this useful material. I want to suggest a topic for an upcoming video that I find interesting. "Array of transistors in parallel" to handle high currents. Simulate it and see its behavior with Ltspice. Again, thanks!!
@FesZElectronics4 жыл бұрын
Hello Diego! Interesting topic, I will keep it in mind! Thanks for the suggestion!
@DiegoColl444 жыл бұрын
@@FesZElectronics Great..!! thank you...!! (congratulations on the style of the back wall. It looks very good! ja!)
@satyaprakashpatra14103 жыл бұрын
Great Bro, Can you please tell me which computer simulation software you are used in this circuit simulation video?
@FesZElectronics3 жыл бұрын
Hello! I use LTspice in all my videos. Its a free simulation software
@satyaprakashpatra14103 жыл бұрын
@@FesZElectronics Thanks bro...
@damianradek28173 жыл бұрын
Very good content. Exellent channel!
@pbaemedan4 жыл бұрын
Thanks for the great video, can we get the .asc file?
@FesZElectronics4 жыл бұрын
Hello Danny! I'm happy you enjoyed the video! In most cases, like with this video, .asc files I usually reserve for my supporters at Patreon as a way to thank them.
@MIsam-fv9kb4 жыл бұрын
Great video 👍 , I like the new wallpaper also
@FesZElectronics4 жыл бұрын
Thanks! I wanted to try some sound proofing and came across the hexagons! They are so soooft :D
@bibinlohi78053 жыл бұрын
Thanks bro
@michaellove79123 жыл бұрын
oh, man, you are awesome
@ryanbrown1722 жыл бұрын
What is the simulation software you are using?
@FesZElectronics2 жыл бұрын
I use LTspice in all my videos. I also have a few tutorials for the program.
@ryanbrown1722 жыл бұрын
@@FesZElectronics thank you for your quick response!
@biswajit6814 жыл бұрын
I did not understand the purpose of using split resistor.could u please explain little bit.
@FesZElectronics4 жыл бұрын
You mean in the base of the transistor? Well, one resistor is there to always limit the current, while the second one has a capacitor shunt - when a pulse is applied, the capacitor is shunting the second resistor, but after it charges, the second resistor reduces base current. The idea is to have a peak current during a transition and then a lower current after the transistor switches
@biswajit6814 жыл бұрын
@@FesZElectronics So u mean we need to select time constant of the of the input circuit in such a way that within input pulse width capacitor should charge fully.once it fully charged then it will act as a open circuit and second resistor will come into picture and it will reduce the base current. correct me if I am wrong.