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In this article, together with Roman (author of the YouTube channel “Open Frime TV”), we will assemble a universal power supply on the IR2153 chip. This is a kind of “Frankenstein” that contains the best qualities from different schemes.
The Internet is full of power supply circuits based on the IR2153 chip. Each of them has some positive features, but the author has not yet encountered a universal scheme. Therefore, it was decided to create such a diagram and show it to you. I think we can go straight to it. So, let's figure it out.
After ordering, the author was impatiently waiting for the payment, and now they have already arrived. We open the parcel, the boards are packed quite well - you can’t complain. We visually inspect them, everything seems to be fine, and immediately proceed to soldering the board.
They are smaller in size and have greater efficiency; however, they are much more difficult to manufacture and often burn out due to incorrect calculation of the transformer or board layout (or something else incorrect). You can make a low-power switching power supply with your own hands if you use one of the microcircuits:
TNY263 at 7.5 W,
TNY264 at 9 W,
TNY265 at 11 W,
TNY266 at 15 W,
TNY267 at 19 W,
TNY268 at 23 W (power for open sources);
use the program, a freely distributed program, PI Expert, which can be downloaded (registration is required for downloading) from the official website www.powerint.com of Power Integrations and route the board according to the recommendations in the documentation or the PI Expert program. The installer of this program takes up about 78MB of memory. At the time of writing this article, to download, you need to go to Design Support-PI Expert TM Design Software-PI Expert Download - fill out the fields and click the "Submit" button (before all this, of course, you need to register and log into your account). The power supply circuit is generated by the program, but you can use the following:
Figure 1 - Switching power supply 9V, 1A
The type of core is determined by its length, for example, if the length is 28mm, then it is an EE28 core.
There are also cores: EE16, EE19, EE20, EE22, etc. from EE5 to EE320 (or maybe there are some others). The transformer must have a gap and be suitable in power. If the program displays an error message, you need to make the necessary corrections. When you first start the program, select file-create from the menu
Select TnySwitch in the "Product Line" field and click "Next"
Click "Add..." select voltage and current and click "OK"
Click "Select"
A diagram will appear in front of you, double-click on the transformer, select the core and click "OK"
Go to the "transformer design" tab and make a transformer as written in the instructions
The windings must be wound exactly turn to turn.
It is very important not to make a mistake with phasing
Go to the "Scheme" tab
You can install a zener diode and a resistor as in the diagram, you can select another zener diode (similar to what was done with a transformer), in this case the program will add a resistor in series with the zener diode, you can also assemble a power supply according to the diagram in the program. A recommended example of PCB layout will appear if you go to the "Layout" tab
It is better to download the program in Russian.
The board can be made using a file from foil fiberglass:
The main thing is to do it carefully and not break the file.
A more detailed example of assembling and testing a block can be seen in the video:
The track from pin 5 of the TNY266 chip to the transformer should be as short as possible.
The DB107 diode bridge in the photo above is upside down. TNY266PN can be inexpensively ordered from the link http://ali.pub/txdeu, the transformer is removed (then rewound) from the board from the TV for free, the remaining parts are not very expensive and most of them can also be removed from the TV or ordered inexpensively.
The power supply is ready! Finally, I remind you that such (return) sources cannot be overloaded and cannot be underloaded. Although there are protections in the scheme, it is better not to abuse them.
DC power supplies are needed not only by radio amateurs. They have a very wide scope of application, and therefore most home craftsmen use them to one degree or another. This article describes the main types of voltage converters, their characteristic differences and applications, and how to make a simple power supply with your own hands.
Doing it yourself will save you a lot of money. Once you understand the device and operating principle, you can easily repair this device.
These devices have a very wide range of applications. Let's look at the main uses. To save battery life, low-voltage power tools are connected to homemade power supplies. Such devices are used for connecting LED lighting devices, installing lighting in rooms with high humidity and danger of electric shock, and for many other purposes not directly related to radio electronics.
Most power supplies convert AC mains voltage of 220 volts into DC voltage of a given value. Moreover, the device is characterized by a large list of operating parameters that must be taken into account when purchasing or designing.
The main operating parameters are output current, voltage and the ability to stabilize and adjust the output voltage. All these converters are classified into two large groups according to the conversion method: analog and pulse devices. These groups of power supplies have strong differences and are easily distinguished from the photo at first glance.
Previously, only analog devices were produced. In them, voltage conversion is carried out using a transformer. Collecting such a source is not difficult. Its scheme is quite simple. It consists of a step-down transformer, a diode bridge and a stabilizing capacitor.
Diodes convert AC voltage to DC voltage. The capacitor further smoothes it out. The disadvantage of such devices is their large dimensions and weight.
A 250-watt transformer weighs several kilograms. In addition, the voltage at the output of such devices can change due to external factors. Therefore, to stabilize the output parameters in such devices, special elements are added to the electronic circuit.
High-power power supplies are manufactured using transformers. It is advisable to use such devices for charging car batteries or for connecting electric drills to save the life of lithium batteries.
The advantage of such a device is the galvanic isolation between the two windings (with the exception of autotransformers). The primary winding connected to the high voltage network has no physical contact with the secondary winding. A reduced voltage is generated on it.
Energy transfer is carried out using an alternating current magnetic field in the metal core of the transformer. If you have minimal knowledge in radio electronics, it is easier to assemble a classic adjustable power supply using a transformer with your own hands.
With the development of electronic technology, it has become possible to produce cheaper semiconductor voltage converters. They are very compact, light in weight and have a very low price. Thanks to this, they became market leaders. Every apartment uses several different power supplies.
Unfortunately, most modern devices do not have galvanic isolation from the power supply. Because of this, quite often people die who use the device while charging a cell phone or other equipment and at the same time take a bath or wash their face.
If safety precautions are followed, there is no danger to a person. These devices are quite low in cost and when they break down, they often do not try to repair them, but purchase a new device. However, if you understand the circuits and operating principles of switching power supplies, you can easily both repair such a power supply and assemble a new device.
Let's look at the design and operating principle of switching power supplies. In such devices, the alternating mains voltage is converted into high-frequency voltage at the input. To transform high-frequency currents, it is not large transformers that are required, but miniature electromagnetic coils. Therefore, such converters easily fit into small housings. For example, they can easily be placed in the plastic socket of an energy-saving lamp.
The layout of such a power supply in a small device does not cause any problems. For reliable operation, it is necessary to provide the possibility of cooling the heating elements of the electronic circuit on special metal radiators. The converted voltage is rectified using high-speed diodes and smoothed at the output filter.
The disadvantage of such devices is the inevitable presence of high-frequency interference at the output of the converter, despite the presence of special filters. In addition, pulsed devices use special output voltage stabilization circuits.
The switching power supply can be purchased as a separate unit, ready for installation in the device. You can also assemble this device yourself using widely available diagrams and instructions for assembling power supplies.
It should be taken into account that self-assembly may be more expensive than a purchased product purchased online in the Asian market. This may be due to the fact that electronic components are sold at a higher markup than the manufacturer's markup in China for the assembly of the product and its delivery. In any case, having understood the structure of such devices, it will be possible not only to assemble such a device yourself, but also, if necessary, to repair it. Such skills will be very useful.
If you want to save money, you can use switching power supplies from personal computers. Often, a faulty personal computer contains a working unit. They require minimal modification before use.
Such power supplies have idle protection. They must be under load at all times. Therefore, in order to avoid shutdown, a constant resistance is included in the load. Such modernized units are used primarily to power household power tools.
To reduce and rectify the mains voltage to 12 V in the traditional way, energy is transferred in series. You will need the blocks shown in the block diagram.
The power transformer at the input reduces the voltage from 220 volts to 15, with a margin, so that later in further circuits it, inevitably losing value during rectification and smoothing, drops just to the required 12 volts. The rectifier is made in the form of a bridge of low-voltage diodes, the result of which is a constant-sign pulsating voltage. It is done in such a way that two half-cycles alternately pass through one pair of diodes, then through the other, and at the output the voltage begins to “twitch” in only one direction. The smoothing circuit contains an inertial element accumulating charges - a high-capacity capacitor. It charges from a pulse and slowly maintains the voltage with its leisurely discharge until the next pulse arrives. This is called smoothing, but additional stabilization of the output voltage is also done so that it is less affected by the load value.
The advantage of such a circuit is that the transformer at the input immediately “decouples” all further circuits from the high input voltage. Only for this you have to pay with a physically large power transformer. In our case, a transformer that supplies a more or less suitable device power, for example, 300 watts (an old TV), should weigh about 4 kg. Well, of course, I put it, such a power supply, on the floor, and it stands without asking for porridge. But what about small devices? Is it really possible to roll it with you on a cart? In addition, a large mass of iron operating at a small load generates low efficiency - about 50%.
Well, the price, proportional to the mass of the device, forces us to come up with something more miniature in all respects.
In switching power supplies, first of all, they got rid of the bulky step-down transformer. The voltage is immediately rectified, and it powers the pulse generator, the voltage of which can then be lowered to any desired level. Moreover, the dimensions of the step-down transformers directly depend on the frequency produced by the generator - the higher the frequency, the smaller the transformer. And then this power, straightened again, is used in the device.
It can be seen that the traditional power supply has moved to the lower floor; in addition, there is feedback that additionally adjusts the inverter (pulse generator)
The power transformer here is pulse, it works after the pulse generator. It is high-frequency, since the generator frequency is about 20–100 kHz. The core material used is not ordinary transformer iron, but ferrimagnets, materials based on structured iron oxides that perform their function better at high frequencies.
The windings of such a transformer have polarity, this plays a role when connecting the beginning and end of the windings.
It is quite possible to make such power supplies very small, as can be seen on the power supplies of energy-saving lamps - they fit into the lamp base.
By the way, the power supply (ballast) of such a lamp can be used for another purpose. Or rather, for its intended purpose, but in a different device, when the lamp - ultra-reliable and economical - still burns out.
The output rectifier after the transformer is made on the basis of Schottky diodes, which have a lower internal capacitance than conventional diodes, and therefore work better at high frequencies.
The feedback circuit calibrates the generator pulses with an error signal, which causes it to produce pulses of longer duration, the more the output voltage differs from the desired nominal value. This transfers more power to the output and equalizes the voltage.
The flyback control unit of the inverter creates a galvanic connection of the output circuit to the input voltage circuit. To get rid of this, optocouplers are used - optical transmission devices, electrical signal-light-electrical signal converters.
Nowadays, modern electronic consumer devices are all produced with switching power supplies. Therefore, it’s easy to make it yourself from parts from other switching power supplies (SMPS), but taking a ready-made unit or charger and slightly altering it to suit your voltage is even easier.
A switching power supply, that is, an inverter power supply, is characterized only by the output voltage and rated power. They all have normal inputs - 220 V. For communication devices, modems, for example, a 24 V switching power supply is often found. Laptops most often take 19 V. All UPSs that have a USB type output produce 5 V. For everything else , for example, LED strips, most often require the familiar and beloved voltage of 12 V from car batteries.
You can take a ready-made switching power supply, reconfiguring it to the required output voltage,
Or you can assemble it yourself on the board, using the simplest circuit.
The elements are easily purchased at circuit component stores.
In addition to assembling the elements on the board, using this description, you can also make a pulse transformer with your own hands.
Since rectangular pulses are “not feng shui” - they have sharp rises and falls in voltage (leading and trailing edges of the pulses), this generates high-frequency interference that can pass through circuits with low capacitance. They usually do not affect the power part of various devices, but in smart circuits they can turn out to be a noticeable unwanted interference.
Often, to power computers, surge protectors and pilots are used, which contain such a function - suppression of high-frequency interference. But pulse power supplies themselves can be a source of such noise signals, so it is necessary to apply additional filtering of such noise at the output.
Switching power supplies are critical to the load ratings; the power they supply should not differ too much, either in excess or in the direction of underestimation. Feedback adjustment is done so that in digital devices that such a power supply supplies with voltage, during operation, the usual power fluctuations for them, occurring from turning on/off some blocks, registers, etc., do not deteriorate normal operation. These oscillations occur around some average power value and should not systematically deviate here or there.
In real power supplies, special protection is provided against operation in an underloaded or overloaded state.
A switching power supply is an inverter system in which alternating voltage is converted to direct voltage, and then high-frequency pulses are formed from it. Such a device is quite expensive and only wealthy people can buy it. All those who do not belong to this category try to make the device with their own hands. To do this, you will need the necessary materials and a 12 V 5A switching power supply circuit.
Before you make a switching power supply with your own hands, you need to study in detail its design features, principle of operation, advantages and disadvantages. Using this information, you can speed up the creation process, as well as make the device better and more durable.
Most often, a homemade switching power supply is made according to a standard design using some important elements. It is used to adjust the input voltage when powering LED lamps or other lighting devices. The block design includes several components:
The switching power supply is characterized by its simplicity of operation. Not only a specialist, but also a beginner with basic knowledge in this area can easily understand it. Because of this, the devices are considered the most affordable and are often used to achieve various purposes. They work as follows:
Feedback can be created in one of two ways. Both of them allow you to perform the assigned functions efficiently and avoid unforeseen situations. Ways to organize feedback:
The process of maintaining the output voltage occurs similarly.
A self-made switching power supply, like any other device, has several advantages. Thanks to them, the design is very popular and is often used in one or another field of human activity. The positive aspects of the power supply include the following factors:
Despite the large number of advantages, the design also has several disadvantages. They must be taken into account, as they will avoid malfunctions and reduce the risk of poor-quality operation of the device. Among the disadvantages are the following:
In order for the device to work correctly and perform the functions assigned to it, a number of rules must be followed. With their help, you can achieve the desired result and reduce the likelihood of errors.
During the manufacture of a switching power supply, you should take into account not only the advice of part manufacturers, but also the recommendations of specialists. They will help beginners avoid most simple mistakes and get the job done in the shortest possible time. Pro Tips:
Before you begin manufacturing the device, you need to prepare all the necessary materials and tools. Thanks to this, you will not be distracted while working to find this or that item. In the process of creating the device you will need:
In addition to the components of the structure, it is necessary to prepare various tools. They will be used to assemble the device, so they must be of high quality and easy to use.
Required tools:
After all the preparatory activities have been completed, you can begin assembling the device with your own hands. The circuit of switching power supplies is drawn up in advance. This work can be done independently or with the help of a specialist.
The first option is much cheaper, but requires the master to have knowledge in the field of electronics and a lot of time.
Step-by-step instruction:
In order to check the assembled pulsed energy source for functionality, you need to perform a few simple steps. They will help identify various problems and errors made during the assembly process. Procedure:
When operating the pulse unit, you must adhere to simple safety rules. They will help to avoid injuries of varying severity and reduce the likelihood of an emergency. Basic precautions:
A pulsed energy source is a useful and necessary device that you can not only buy ready-made, but also make it yourself. The second option is more popular, as it allows you to get a high-quality device with minimal financial and time costs.
By following professional advice and safety rules, you can significantly reduce the risk of injury and avoid accidents.
