Switching Regulators - Solid-state Devices and Analog Circuits - Day 9, Part 7

Vocademy - Free Vocational Education
Switching regulators are more efficient than linear regulators.

[@samsam100b]

Nice 🎉

[@imadjihad9295]

Great , and i like it ,, save your whiteboard is too small master !!!, please use bigger one .

[@AbhijitGangoly]

Most of the SMPSs (switching power supply) do use transformers. Very small one, but still transformers. I assume these transformers do used to prevent mains AC voltage to enter low voltage output during any faulty conditions. Though they "Leak" some voltage from primary to secondary due to parasitic capacitance. This is usually filtered out by connecting a non polarised capacitor from the negative output terminal of the secondary to the earthing or grounding terminal of the mains connector.

[@THEOFFGRIDMOUNTAINHOMESTEAD]

Love your channel, trying to learn more about building/repairing some of my own components. Question, could you possibly “tear down” a commercial battery charger/converter (like IOTA, Victron, Aims power etc) and show all the components or repair a broken battery charger/troubleshooting etc? Thank you!

[@cookiii]

Wonderful explanation, well presented :)

[@xl1803]

Superb ❤❤

[@fabientuizat1129]

Merci !!! et avec un 431 a la place de la zener le switch devient quoi !! merci pour vos propos instructifs !!

[@junkerzn7312]

One thing I will note is that some power supplies are isolated and some power supplies are not isolated. Its probably like 70% isolated and 30% non-isolated out in the world (guestimate). For example, a USB-C PD port plugged into the wall is isolated. A bench supply is not usually isolated but it can be. Supplies for outdoor use are isolated. And most high-end commercial supplies (such as "Mean Well" supplies) are isolated. The power supply for POE+ is isolated. Etc. Isolated supplies still have a transformer, albeit a small one. The transformer does the isolation. It can be 1:1, but usually there is some sort of step-down... just not all the way down to 20V. Usually there is a little step-down, like to 60V or so, just so the voltage rating of the circuit components can be lower and so cheaper transistors or FETs can be used. The current is low so this allows the transformer to remain small. The interesting thing about an isolated supply is that there is no path for the electrons via earth or frame-ground. The only return path for the electrons are via the supply's positive lead and the only source for the electrons are via the supply's negative lead. This makes it more difficult to accidentally short the supply or to accidentally electrocute oneself, but at the same time it also means that the supply can have faults (faults to earth for example) that go undetected unless the supply itself has a detection circuit for it (a big 10M or some such resistor between the frame ground and the supply output negative that it measures looking for current flow). -Matt

[@mikesradiorepair]

If you have a bench power supply that has the output tied to ground then it's best place to live is a junk bin. I probably have 40 or more lab power supplies ranging from vacuum tube era 3,000 Volt supplies to linear power supplies to current production switch mode power supplies. I have never seen one that had the output tied to the chassis / earth ground. All of them are isolated. However several of the supplies have three terminals. Positive, negative and a earth ground connection. The earth ground connection has a tab that can be swung over to jump the negative terminal to earth ground "if" required.

[@TheVendan]

As i said i added the output voltage if op amp to input of transistor and simulation of this circuit i can get negative 210 voltage is it correct output

[@TheVendan]

Hi sir,have to give op amp output to input to the transistor.is it correct? and from that we have to get switched voltage output

[@farhadsaberi]

where's the link to the video that explains the op-amp configuration? thanks

[@grzesiek1x]

Yes they are very popular everywhere but annoying for radio amateurs! It produces so much noise that I can't listen to my own built AM radio near the computer or monitor screen on...

[@DixieGeezer]

I thought I knew electricity flow but a KZbin by Veritasium has confused me. Could you discuss electron flow in a conductor.. Is electricity a wave or electron flow?

[@junkerzn7312]

Current is just the flow of electrons. That is, current is just the amount of charge passing through a volume of space. Every electron have the same amount of charge. One electron == 1 unit of charge. Counting the electrons passing through a volume of space is a measurement of current. Current alone is not power ... it does not perform work just by itself. For example, a current flowing in a loop in a super-conductor is not doing any work. Voltage is basically just the difference in charge density between two points (with some caveats). Charge density, in turn, is simply the density of electrons minus the density of protons in a volume of space. That is, squeezing electrons together so they are at a higher density than the protons in nearby atoms is what creates charge density. The absolute measure of the charge density at any given point IS NOT VOLTAGE. Voltage alone is also not power... it does not perform work just by itself. For example, a power supply outputting a voltage but not connected to anything is not using any power or doing any work (ignoring vampire power consumption inside the power supply). (For voltage, think of two magnets on two sides of a piece of wood. The distance between the magnets causes a force which is "potential energy"... not work, not power, but potential energy. That is effectively what a voltage in an electric circuit is, but caused by the electric potential between electrons that are being packed together or pulled apart from each other, and not the magnetic field). -- Ok. So now back to Veritasium. When it comes to "electricity", power can be transmitted three different ways. The first is (current * voltage) inside the wire. That is straight-forward I hope. The second way is through direction emission of an EM wave... a changing electric field. A static electric field doesn't transmit power. Only a changing electric field. The third is coupling through a magnetic field (transformer, inductor). For the Veritasium example, massive changes in the voltage from "closing the switch" emits a fairly powerful EM wave that can coupled across the wires and cause electrons to move on the return wire very quickly (speed of light as the crow flies). But this EM wave is momentary. The propagation of the changing potential through the wire, however, creates more or less a continuously changing EM wave that can couple across. So as the voltage change propagates a good chunk of power continues to be transmitted via the field. Once the huge changes in potential (voltage) have completely propogated through the wire, however, the EM wave being emitted by the wire due to the current is much much smaller.... there are no longer huge changes in voltage propagating along the wire. So NOW nearly all the power being transmitted is being transmitted through the wire, not across the gap. Remember that power in a circuit requires current (flowing electrons) AND voltage (electric potential). Also... fun fact... power is relative too. You are measuring power as (voltage x current) through a wire, but "voltage" is a measurement against some other part of the circuit, such as ground. So power is relative. The heat generated by the circuit is entirely due to the current and resistance and nothing else (power = I * I * R = heat generated when R is the resistance of the circuit and no other forms of energy are involved, like acceleration). There is a lot more to it than this, but that should be enough to understand what is going on. -Matt

[@DeeegerD]

Why didn't yoú finish the linear supply series? Disappointing. I find your videos much like when I sat in a class room bored to tears as they taught too slowly.

[@ernieschatz3783]

I really wish people would just cut to the chase with the switching part. A switching regulator 100% will not use a relay or any other physical switch contact. You're just putting off what you know you'll have to teach sooner or later. Big waste of time IMO.