Mr.T's Design Graveyard

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@xiaomiphone9349 Күн бұрын

Very nice tnku

@smartpowerelectronics8779 18 сағат бұрын

@@xiaomiphone9349you are welcome 😊

@we-are-electric1445 Күн бұрын

What version of USB were you using ? Surely, it would only work with USB 1.1 if it is sampling at 24 MHz !!

@smartpowerelectronics8779 Күн бұрын

@@we-are-electric1445 you are correct, this logic probe cannot analyze USB2 or 3 full speed devices. It can work for human input devices “HID” like mouse or keyboard because they run at 12MHz

@we-are-electric1445 Күн бұрын

@@smartpowerelectronics8779 Yes ! It looks a bit limited. I was looking to use it on ST32 Microelectronics ARM based development boards but it looks like I am going to have to look for one running at very low clock speeds !! 😁

@AdamTheBot 2 күн бұрын

IDK why it's not working .

@smartpowerelectronics8779 Күн бұрын

@@AdamTheBot that is frustrating, did you check all voltages pin by pin? What I of the do is test by attaching an LED with 1k at the output and then use a wire to touch the input to 12V and 0 V while watching the LED😆

@kirishima638 2 күн бұрын

Is there a particular reason you are still using Arduino IDE 1.8?

@smartpowerelectronics8779 Күн бұрын

@@kirishima638 yes, it 1.8 is portable so I can copy the whole folder to any computer and use it, 2.0 cannot be used portable . See my vid kzbin.info/www/bejne/laOlgHh-ptN5kKMsi=KI7MqGCpzaQoB-Ix

@kirishima638 2 күн бұрын

Exactly what I needed thank you. NOTHINGS wrong with using global variables for small programs. They actually simplify the code massively and make it easier to understand.

@smartpowerelectronics8779 Күн бұрын

@@kirishima638 thanks man, I am a power supply designer so not the greatest at software, but if I would start my studies now I would go for embedded software, it is really interesting!

@Scrogan 2 күн бұрын

Looks like there are some improvements to be made. Looking at the internal schematic of a 555, you’ve got the Set and Clear pins of the SR latch both held high at once, which isn’t really in-spec. I think. Also you really should put a resistor on the reset pin as to not be undefined when the MCU is in a startup state.

@soupflood 2 күн бұрын

If the microcontroller crashes, the 555 output on pin 3 gets high and that's not desirable; when the input is disconnected, the output should be low. Do you know how that bug could be solved?

@Scrogan 2 күн бұрын

@@soupflood if the MCU output goes high-z (like it does when it’s initialising) then you could avoid it by having a pull-down resistor on the reset pin. But if the MCU output goes high and stays high, there’s nothing you can do besides put a fuse on your power input.

@soupflood 2 күн бұрын

@@Scrogan if the 555 timer's input (pin 4 reset) gets disconnected (or the MCU crashes) the 555's pin 3 output gets high. That's a 555 specific bug in this setup. I already tried resistor across the 555 input (between reset and ground) and it didn't work. The fuse wouldn't solve this either

@esoterex 3 күн бұрын

I'm using the TLC555CP the CMOS version for a MOSFET driver for over 30 years. Not only that, I use the 555 also as the PWM controller, fixed on time, variable frequency, including the soft start function. It is one of my early designs and still in use after 30 years. Manufacture hundreds of DC to DC converters a month using it. Not everybody can use that topology but in my case is just what the doctor ordered.

@soupflood 2 күн бұрын

If the microcontroller crashes, the 555 output on pin 3 gets high and that's not desirable; when its input is disconnected, the output should be low. Do you know how that bug could be solved?

@smartpowerelectronics8779 Күн бұрын

@@esoterex yes the 555 is used in professional products, I worked on one HID lamp driver for office projectors with the 200W buck controlled with an NE556😂, built a few million pieces with high quality. Was the current output of the TLC not too low? Perfect ZVS?

@ABDERRAHIMELKOUFI 3 күн бұрын

Thomas Young

@soupflood 3 күн бұрын

I'm glad you uploaded this excellent video. Maybe someone will also sort out the 555's open input bug (open input results in high output on pin 3). I still find it fascinating that 2 components which are considered toys by most engineers can perform so well in this configuration. I use it to drive 2 paralleled TBI injectors in a 90's Chevrolet, by the way. It works great (unless the Arduino crashes, but it's mostly about filtering resistors, capacitors and keeping spark plug wires away from the Arduino cables). The Arduino is fed by a dedicated external 5V regulator and the 555 is fed by another 12V regulator (for increased reliability). Have a good day!

3 күн бұрын

3:35 USB pinout is wrong. After Vcc, it must be D-. not D+

@Tntdruid 4 күн бұрын

Use esphome :)

@DrTRonik 4 күн бұрын

🙏

@Jim_One-wl4ke 4 күн бұрын

Another well presented video for us electronics learning & exploring enthusiasts. Thank you very much for making such a good video and sharing your knowledge ❤

@Jim_One-wl4ke 4 күн бұрын

Wow 🤩. That’s a brilliant idea. Thank you ❤for sharing

@smartpowerelectronics8779 4 күн бұрын

You’re welcome 😊

@AdityaMehendale 4 күн бұрын

Hah, slim bedacht :)

@killersmile7153 5 күн бұрын

Wow great tutorial. Can I ask about the #3 level shift circuit if the R-load/output is paralleled to high capacitance capacitor can it still charge the bootstrp capacitor during off state of HO switch while the output capacitor still have some charge on it if VS need to be in GND level voltage when High side is off to charge bootcap.

@ColinMcCormack 5 күн бұрын

What a great idea. Thanks!

@smartpowerelectronics8779 5 күн бұрын

Glad it was helpful!

@wt29 5 күн бұрын

Nice project but have you heard of GitHub?

@jorinc 6 күн бұрын

Thanks but please clarify that it only generates pulse (square) signals, because the term Signal Generator usually means that other forms such as Sine, Triangle, Sawtooth, etc. can also be made.

@smartpowerelectronics8779 5 күн бұрын

Thank you for the reminder, I changed the title of the video to "PWM signal generator"

@jorinc 5 күн бұрын

Thank you for making the changes, but you didn’t have to. It is very considerate of you, which is very rare these days. You are a great teacher and a good person.

@smartpowerelectronics8779 5 күн бұрын

Even though I do this channel just for fun, I try to keep a high standard 😊

@EdukasiDIYTutorial-ec9ke 6 күн бұрын

Great... it will be usefull

@smartpowerelectronics8779 5 күн бұрын

thank you!

@lezbriddon 6 күн бұрын

Add one of the cheap 'nokia lcd' screens and some buttons and this is a great little bench generator project.

@smartpowerelectronics8779 5 күн бұрын

Thank you! You are right, I just tried to keep it as simple as possible 🙂

@smartpowerelectronics8779 4 күн бұрын

github.com/tricksofali/Arduino-square-wave-generator

@kirishima638 2 күн бұрын

@@smartpowerelectronics8779this is awesome!

@alo1236546 2 күн бұрын

Hc 05 bluetooth module is fine

@pierpa_76pierpaolo 6 күн бұрын

Maybe that's what I was looking for. It should do the trick for me. I'm interested in running a motor, lamp with pwm signal. Whereas for a motor I would like it "independent" and manage it through the digital signal. I don't know if I explained myself. :)

@soupflood 2 күн бұрын

This general setup works well for PWM driving low impedance (1 ohm) injectors in an automobile, it's what I've been using it for. The big issue with it is that if for some reason the Arduino crashes, the 555 output will become High. That translates to a steady full flow of fuel into the engine (drowning). If you have any idea how to fix it, please share.

@mostafanfs 8 күн бұрын

Could we use 555 to drive a p channel mosfet too? As a high side switch capable of switching the power to another circuit

@BVRamesh100 9 күн бұрын

Can the circuit be tested for 1% PWM and 99% PWM at 100 kHz?

@smartpowerelectronics8779 9 күн бұрын

@@BVRamesh100 the off delay is about 180ns, 100k 1% is only 100ns so unfortunately it cannot work

@asmanfarbehar9402 10 күн бұрын

ممنونم ❤

@smartpowerelectronics8779 8 күн бұрын

You are welcome 🙂

@depressivepumpkin7312 10 күн бұрын

dank u wel

@smartpowerelectronics8779 8 күн бұрын

ik hoop dat je nu een gelukkige pompoen bent!

@KennethTanFotografie 10 күн бұрын

Excellente tutorial. Alsof ik terug op MTS ben bij mijn favorite docent.

@Electronzap 10 күн бұрын

Nice :)

@hamidsk2573 10 күн бұрын

Awesome technical content, theory and practical science meet here ,thank you very much do you have any future plans to make a video about h-bridge or bldc mosfet switching performance, similar to your MOSFET series

@SanjaySharma-pw6ww 10 күн бұрын

Very nice video. I was pleased

@HamzaKhwayre 11 күн бұрын

شكرا لكم

@stephengray9207 11 күн бұрын

Hmmm, sure its one way. You could use one or two super cheap transistors, a logic gate, a schmidt trigger, a comparator, an opamp, all sorts! but its OK that you did this.... but its not the only way. The right method depends on space and cost limitations.

@doganertan7259 11 күн бұрын

Really great and explanatory video ı really liked your explanation. But what happens if we were to do like an H bridge configuration? This time we need drain voltage + gate thresold voltage to use the mosfet on the High side right? That would mean 12v is not sufficient and maximum 16v rating of ne555 is also not sufficient. Or am ı wrong can you please answer me ı don't know and ı am just asking.

@smartpowerelectronics8779 11 күн бұрын

Thank you! For H-Bridge you will need to make a bootstrap supply of 12V like in this video: kzbin.info/www/bejne/g2bPdoeXpq5sgK8. Suggest you use the IC solution, much easier and robust. You can also use a motor drive IC like ST's L293D for low voltages and frequencies.

@doganertan7259 11 күн бұрын

@@smartpowerelectronics8779 ı am trying to design a brushless ESC with microcontrollers and wanted to make a H bridge first. Most Motor driver IC's cannot handle a lot of current and voltage and ı don't want to throw an IC to the problem to be honest ı want to learn how to do it myself. But Thanks for your answer you have some really good content. ❤

@paradiselost9946 8 күн бұрын

@@doganertan7259 bootstrapped... i also prefer discrete components over ICs... only issue with the charge pump bootstrap in a h-bridge is it cant be used for say, direction control on a motor? all good as a driver, for PWM, but they cant be constantly "on" (or "off"?) as the charge pump capacitor does slowly discharge. depending on the value, you still have approximately half a minute to a day or two though! but as the value gets larger it also means it requires a longer "dwell" time to recharge that capacitor... so you keep them small for high speed operation... as most H bridges run PWM at a reasonable frequency, its not an issue. some people do use them for polarity reversal though. better to use a single throw double pole switch/relay for that application.

@doganertan7259 8 күн бұрын

@@paradiselost9946 I saw a lot of commercial ESC models don't have a mosfet driver inside. Most of them uses a discrete circuit it seems. Using discrete components are a lot cheaper than using driver IC's. Discrete circuits can "off" the mosfet but they can't make the mosfet stay "on" that long. For a High side mosfet can we just put a boost converter circuit and switch it with a transistor on the mosfets gate? Because in my country there is a boost converter called mt3608 that is cheaper than that driver IC and ı did not see any circuits online about using a boost converter. Or there is another method that ı don't know?

@paradiselost9946 8 күн бұрын

@@doganertan7259 go look up "high side charge pump". diode, capacitor, and a bjt/opto (preferable). its pretty simple. theres a few good schematics for full discrete h-bridges with charge pumps. boost convertor is leading away from simplicity ;)

@lezbriddon 11 күн бұрын

So as far as the mosfet is concerned its just seeing the npn and pnp switching transistor in the 555. I would just use a a pair of transistors and not waste a 555. in fact real mosfet driver IC's are possibly same cost as a 555. saw a guy use some optocouplers a few years ago for driving P channel fets from logic lines.

@smartpowerelectronics8779 11 күн бұрын

You are clearly a professional! The transistor pair will give you the current gain, however for the voltage gain you need a 3d transistor, see this video: kzbin.info/www/bejne/raeXpnSwbauJaNk .

@AdityaMehendale 11 күн бұрын

If you take a complementary pair - say BC547 and BC 557, and put them in emitter-follower, you can achieve the same effect with - Lower pin-count - Lower cost - Lower quiescent current - Better performance. 555s are good to learn the basics, as illustrated in the fantastic book by Forrest M. Mims III, but let's leave it at that.

@smartpowerelectronics8779 11 күн бұрын

The totem pole will give you the current gain, for the voltage gain you need a 3d transistor, see this video: kzbin.info/www/bejne/raeXpnSwbauJaNk

@PhillipRhodes 9 күн бұрын

No, let's not "leave it at that." It's better to have knowledge of all the different ways to use all the tools in your toolbox (so to speak) as you can never anticipate all the circumstances that can arise. Maybe you're in the middle of a build and don't *have* BC547 and BC557 transistors available, nor any kind of dedicated MOSFET driver... but do have a box full of 555's. Then it could very easily be the case that the 555 is the perfect solution - in context. I don't think anybody is saying that a 555 should be the MOSFET driver of choice, but knowing that it's capable of performing that function is potentially a damn handy bit of knowledge. It's just another arrow in the quiver.

@AdityaMehendale 8 күн бұрын

@@PhillipRhodes To be clear, I'm not talking about "could" but rather "should".

@jensschroder8214 12 күн бұрын

Maybe the NE555 drives a serial RS232 with 12V = Low and 0V = High? Or an ATMega HV programming? This requires 12V on the reset pin of the ATMega. Then you can still delete the program from a locked IC and reset the fuses to normal.

@smartpowerelectronics8779 11 күн бұрын

Good idea, it is fast enough for RS232, I have never tried Atmega HV programming, did not know you can use it to erase a locked IC, so I learned something today, thank you!

@devilvortex1 8 күн бұрын

can you share the code?

@danielmantione 7 күн бұрын

@@smartpowerelectronics8779 Een Atmega die op slot zit, stop ik altijd mijn TL866, die met hoog voltage de boel weer op poten kan zetten.

@jensschroder8214 12 күн бұрын

This doesn't work with the B555 from GDR production. On the NE555, the Set input is overruled by the Reset input. However, with the B555 the Reset input is overruled by the Set pin. The reason is that the NE555 takes the /Q output from flipflop and inverts it again in the driver stage. That's why Reset is dominant. However, the B555 takes the Q output from flipflop and does not invert it in the driver stage. That's why Set is dominant. For most applications, however, this difference is irrelevant. Most 555 clones do it like the NE555.

@smartpowerelectronics8779 11 күн бұрын

Thank you, you seem to be an NE555 expert! I tried all the 555's I had lying around and they worked OK except the TLC555, but there are many variants of the 555....

@romancharak3675 12 күн бұрын

This will work nicely even if you don't require PWM, just ON &OFF states. Thank you for showing us the results of your testing.

@smartpowerelectronics8779 11 күн бұрын

Thank you!

@alexloktionoff6833 12 күн бұрын

Nice forgotten idea! One 555 costs about as one middle powerful transistor. So for 3.3v controllers it looks like a winner - no additional components.

@smartpowerelectronics8779 11 күн бұрын

Thanks, indeed. I use it already in a project

@alexloktionoff6833 10 күн бұрын

It’s possible to use 555 in a high side driver for 12v, just use one more 555 as a voltage doubler with diode and capacitor. So using cheap PC817 optocopler we can switch +12v high power loads

@alexloktionoff6833 12 күн бұрын

You can connect 555 DIS to Q and get even more current to close MOSFET Gate faster. Usually MOSFETS drive inductive loads so fast close is more important than fast open.

@smartpowerelectronics8779 11 күн бұрын

That is a good idea, I did not think of that!

@pepe6666 12 күн бұрын

im quite confused when you said you were gonna build the circuit. i just saw a load there with a reverse diode, then you added a transistor and stuff. i got lost after that point.

@smartpowerelectronics8779 12 күн бұрын

The transistor, 4k7 resistor, zener diode and the 100nF capacitor are added to make 12Volt for the NE555. You can also use a lab power supply for that. I wanted to show exactly how I test the circuit to make sure I show the actual performance :-)

@derrickadusei7987 13 күн бұрын

great video . pls what is the name of your simulator

@smartpowerelectronics8779 12 күн бұрын

@@derrickadusei7987 it is simetrix, simplis , the free version

@Steven-lz1jo 13 күн бұрын

Could you please share the source where these circuits appear?

@smartpowerelectronics8779 13 күн бұрын

Hi Steven, these are circuits from my memory from the 90's, I just verified them by simulating and building them. I did not have practical experience with the 3d circuit (cascode), I heard of it before and found one reference here: electronics.stackexchange.com/questions/264142/drive-a-mosfet-via-bjt MOSFET driving is very specific knowledge, so it is not easy to find good reference information. You can check application notes of Texas Instruments, they have some great material like this pdf: www.ti.com/lit/ml/slua618a/slua618a.pdf?ts=1722369784772

@AdamTheBot 15 күн бұрын

Tried but don't know why it's always on and the two bc547 are just getting hot .

@smartpowerelectronics8779 14 күн бұрын

Was it the 3d circuit? (cascode with 2 x BC547) Please check the 12V supply and the transistors (Take the out & check B-->E and B-->C with multimeter diode test mode, should be 0.6-0.7V). When all parts are ok, also voltages make sense, connect the input to 12V, then to 0V (gnd) and check the output (with a LED+2k or mutimeter) - does the output go up and down?

@AdamTheBot 14 күн бұрын

@@smartpowerelectronics8779 Will try, thanks for the reply !