**The World of Gate-Drive Transformers**

Creating a DIY Gate-Drive Transformer is a fascinating project that requires attention to detail and a good understanding of electrical engineering principles. In this article, we will delve into the world of Gate-Drive Transformers, explore their importance in modern electronics, and provide a step-by-step guide on how to build one.

**The Importance of Gate-Drive Transformers**

Gate-Drive Transformers are used to drive high-power MOSFETs and other electronic components with high-frequency signals. They play a crucial role in modern electronics, particularly in the field of power electronics. The transformer's primary function is to provide a safe and efficient way to switch on and off high-power devices, reducing the risk of electrical shock and damage to equipment.

A well-designed Gate-Drive Transformer can improve the performance of a tesla coil, LED driver, or any other high-power electronic circuit. By using a Gate-Drive Transformer, you can reduce the risk of electrical shock, improve efficiency, and increase the lifespan of your equipment.

**The DIY Gate-Drive Transformer Project**

To build a DIY Gate-Drive Transformer, you will need some basic materials and tools, including a ferrite core, conductors with similar cross-section areas, and a transformer design software. The process involves winding the primary and secondary coils around the ferrite core and designing the transformer to meet your specific needs.

One of the key challenges when building a DIY Gate-Drive Transformer is selecting the right materials for the job. You will need to choose a ferrite material that has low leakage inductance and high magnetic permeability, as well as conductors with similar cross-section areas to ensure efficient energy transfer.

**The Benefits of Using a Commercial Solution**

While building a DIY Gate-Drive Transformer can be a fun and educational project, using a commercial solution is often the better option. Commercial Gate-Drive Transformers are designed and manufactured by experienced engineers who have optimized their design for efficiency, reliability, and safety.

Commercial Gate-Drive Transformers also offer several advantages over DIY versions, including lower leakage inductance, higher magnetic permeability, and improved thermal management. Additionally, commercial transformers are often tested and certified to meet specific industry standards, reducing the risk of electrical shock or equipment damage.

**The Design Process**

When designing a Gate-Drive Transformer, you will need to consider several factors, including the frequency range, inductance value, and voltage applied to the transformer. The design process involves calculating the required inductance value using specialized software or formulas, selecting a suitable ferrite material, and determining the number of turns for the primary and secondary coils.

The periodic time, which is inversely proportional to the frequency, will determine whether the transformer reaches its magnetic saturation point during switching. By adjusting the design parameters, you can optimize the transformer's performance and ensure reliable operation.

**Parasitic Components**

While designing a Gate-Drive Transformer, it is essential to consider parasitic components that can affect the output signal, such as leakage inductance and winding capacitance. These components can lead to distortions of the output signal, phase delay, noise, or ringing.

To minimize these effects, you can use techniques such as adding damping resistors to the primary and secondary sides, using diodes on the secondary side to fasten discharge, and incorporating freewheeling diodes between the drain and source of the MOSFET. However, even with careful design and component selection, parasitic components may still affect the output signal.

**Real-World Application**

In our experiment, we used a commercial Gate-Drive Transformer to drive an LED and observe its performance at different frequencies. We started by testing the transformer at 180 kHz and observed that it worked acceptably well with minimal distortion or noise.

However, when we lowered the frequency to 20 kHz, the waveform became problematic, and the transformer reached its magnetic saturation point. This taught us the importance of designing a Gate-Drive Transformer for specific applications and considering factors such as frequency range, inductance value, and voltage applied to the transformer.

**Conclusion**

In conclusion, creating a DIY Gate-Drive Transformer is an exciting project that requires attention to detail and a good understanding of electrical engineering principles. While using a commercial solution may be more efficient and reliable, building a DIY version can be a fun and educational experience.

By following our step-by-step guide and considering factors such as frequency range, inductance value, and voltage applied to the transformer, you can design a Gate-Drive Transformer that meets your specific needs. Remember to also consider parasitic components and take steps to minimize their effects on the output signal.

**Final Thoughts**

The use of Gate-Drive Transformers has revolutionized modern electronics, enabling efficient and reliable switching of high-power devices. By understanding the basics of Gate-Drive Transformers and designing them for specific applications, you can unlock the full potential of your equipment and create innovative electronic circuits that transform our world.

WEBVTTKind: captionsLanguage: enA while ago I ordered myself this Tesla CoilKit from Ebay.And I have to admit that it was not supercheap.But the shown electric spark pictures werejust too fascinating to not buy it; I meanI was never capable of creating such longsparks while I built my own DIY Tesla Coilduring a 3 part video series.But anyway, after having a closer look atthe secondary coil, primary coil and PCB;so basically pretty much everything the kitcame with, I was rather satisfied with thequality and thus I continued by printing the15 pages of the manual which answered allquestions concerning the build process andhow to use it.So next I did what I can do best and thatis soldering components to a PCB which tookme a total of around 3 hours.After the circuit was done, I assembled thetesla coil, connected it to the PCB, used12V of my lab bench power supply to powerthe control electronics and utilized a variabletransformer to power the half-bridge aka theprimary coil.And as you can see at an input voltage ofmerely 25V AC, the tesla coil was alreadycapable of creating pretty decent arcs whichwere more impressive than those of my oldtesla coil.But why is that when we consider that thedriver of my old and new tesla coil followa pretty similar functional principle?Maybe this component is the answer which isknow as a Gate-Drive Transformer and it isused to basically control the MOSFETs in thehalf-bridge.I didn't use such a component for my old teslacoil driver since I was using two BootstrappingDriver ICs instead to control the MOSFETs.And if you are now asking yourself how thebasics of driving MOSFETs look like and whatBootstrapping is then definitely watch Part1 of this MOSFET Driver video series.But getting back to the topic because in thisvideo we will be finding out when to use Gate-DriveTransformers, how they function, how to buildone by ourselves and why using a commercialone often makes more sense.And at the end we will finally be capableto answer the question whether the Gate-DriveTransformer is truly responsible for the betterperformance of the new Tesla coil.Let's get startedThis video is sponsored by the Würth ElektronikeiSos group.I already talked about the problem of highside switching an N-Channel MOSFET in a half-bridgeduring part 1 of this video series.But as a refresher we can say that due tothe floating GND of the upper MOSFET, we requirea higher voltage at the gate in order to completelyswitch it on, which is most of the time abovethe supply voltage.That is why we use the principle of Bootstrappingin order to create such a higher voltage.But you can actually avoid the problem ofthe floating GND if you control the gate ofthe MOSFET with a galvanically isolated voltagesource like for example a transformer.In this case the reference voltage potentialat the junction point of the MOSFETs doesnot increase for the isolated voltage sourceand thus we only require a fitting voltagesignal.We also get the advantage that the controland power sections of the circuit are nowgalvanically isolated from one another.That means that even when the power electronicsuse a higher voltage which might go up tomains voltage, you do not have to be scaredwhile for example measuring something in thecontrol electronics section since there isno potential difference between both sides.That is why this potential-free or galvanicallyisolated driving is not only simpler but alsosafer.And that is the moment our Gate-Drive Transformercomes into play which is obviously used forsuch driving tasks.In the case of the new tesla coil driver wecan see that it only consists of a ferritetoroid around which 3 conductors are woundwith a total amount of 13 windings.That means we are dealing with a transformerwith one primary side and two secondary sideswhich all come with the same winding directionand a winding relation of 1:1:1.Now If I for example supply the primary sidewith a voltage signal of +/- 5V then bothsecondary sides will spit out the same voltagesignal with the same waveform, potential andamplitude.This is of course only possible if the transformerdoes not reach its magnetic saturation duringthis process.And if you have no idea what magnetic saturationis or want to learn more about transformersthen make sure watch my video about the subject.But anyway, with the voltages being transmittedto the secondary side, we basically createda galvanically isolated voltage source whichwe can use to control the gate of a MOSFET.And if we swap the conductors for the secondsecondary side, we can even control the secondlower MOSFET at the same time with an oppositetiming in comparison to the upper MOSFET whichis of course necessary for a half bridge.But enough already of the theory, why don'twe just have a look at the voltages of theprimary and secondary sides of the Gate-DriveTransformer on the oscilloscope.Now we can easily see that the secondary sidevoltages come with a frequency of 184kHz aswell as with high enough amplitudes in orderto switch the MOSFETs without any problems,perfect.The only minor problem is the small voltageovershoot which occurs when the polarity changes;but we could easily damp those by adding adamping resistor to the primary and or secondaryside.Other than that we could also add a diodeon the secondary side to faster dischargethe gate, two Zener diodes between the gateand source in order to get rid of over-voltagesand a freewheeling diode between drain andsource to also prevent over-voltages acrossthe MOSFET.On the primary side however we only need anadditional capacitor in order to avert thebuild up of a DC voltage which would leadto an early magnetic saturation of the core.And since we are now familiar with how theutilized Gate-Drive Transformer functionsand how it is being used in the circuit; whydon't we try to make our own?I mean I got a pretty similar ferrite corelying around as well as some conductors witha similar cross section area.So I twisted two wires around one anotherand wound them around the ferrite core justlike it was done with the tesla coil Gate-DriveTransformer.And the result actually didn't look half bad.So for a small test I connected the primaryside with a capacitor and a function generatorthat spat out a square wave voltage with afrequency of 180kHz.If we now connect the secondary side withthe MOSFET LED example from part 1 of thisvideo series then we can not only see thatthe LED lit up without a problem but alsothat the waveforms on the oscilloscope lookedrather promising.I mean they were not perfect since the maximumvoltage values decreased a bit during theiron time but they were still useable.BUT, and here is the problem, if we now lowerthe frequency, we can observe how the waveformslowly becomes more and more problematic andat a frequency of 20kHz it was pretty muchunusable since the transformer reached itmagnetic saturation.The culprit for such a problem is of coursethe Design of our DIY Gate-Drive Transformer.Because before actually winding one of those,we have to think about at which frequencywe want to use it, which inductance valuewe require and what voltage will be appliedto it.Through those decisions it is determined whatkind of ferrite material we have to use, howbig the cross section of the core has to be,how many turns the primary and secondary sidehas to come with and much much more; whichcan all be calculated with relatively complicatedequations.And even if you theoretically and practicallycreated the perfect Gate-Drive Transformerthen there still can be problems due to theexistence of parasitic components like theleakage inductance and the winding capacitance.Those can lead to distortions of the outputsignal like a phase delay, noise, overshootsor ringing.So what do you do if you want to avoid longand difficult calculations and reduce parasiticcomponents to a minimum?Correct!You simply browse through the available Gate-DriveTransformers on the Würth Elektronik eiSosgroup website.This one for example comes with a very lowleakage inductance as well as a low windingcapacitance.And if you are wondering whether the transformerreaches its magnetic saturation during switchingwith for example a voltage of 5V; then allwe have to look for is the Vµs value whichis in this case 102.To get the minimum frequency we simply haveto double the value and divide it by 5V inorder to calculate the periodic time whichwe then can convert to a frequency which isaround 24.5kHz.That means we can connect the commercial Gate-DriveTransformer carefree with the MOSFET, LEDexample and see that it works acceptably wellwith the just calculated frequency.Of course if we go back to the 180kHz frequency,we can observe that the commercial solutionperforms quite a bit better than our DIY version.And with that being said it should now beclear how you can make your own DIY Gate-DriveTransformer and why using a commercial solutionis pretty much always more efficient.Now let's get back to the initial questionwhether the driver with Gate-Drive Transformeris responsible for the better performanceof the new tesla coil.And my answer is that there is a big possibilitybecause as you can see my old tesla coil doesin fact perform quite a bit better with thenew driver.And with that being said I hope you enjoyedthis video about Gate-Drive Transformers whichmeans that now you should be familiar withall the basics when it comes to driving MOSFETs.As always don't forget to like, share, subscribeand hit the notification bell.Stay creative and I will see you next time!