power adapters often have a role secondary and low priorigiven when designing a new producto. However, A system is only as good as its weakest link and the Customizedexternal adapter or power supply externa it must offer the same levels of quality and benefits as the final product to prevent the customer from feeling dissatisfied. The adapter not only supplies voltios y amperiouss, but must also meet the standards interncnationalis established safety and compatibility electromagnetética, may vargo depending on the ceiling lampción end and area geographicafica. otheros byámetros as efficiencyia, regulatesción, maximum power output, retention by AC failure, temperature, moisture ingress rating, no-load/standby losses and isética, among others, they can also be essential for the usabilitydad y the correct operation of the final team.
This Articleicle explainedca the main specifications along with others not so well known of a power adapter and why there may be a significant variesción in size and costand between models that for the rest it seemsn have values similares. Symbols that sometimes seem confusing are explained, as well as some errors a avoid when choose a Customizedlove. Examples of available models are provided in order to provesr the most advanced designs and the benefits for the user.
Rsystem power requirements
When the design of a new productor system power requirements arise. One pArticlequality la decision making can be focused on adding a power supply discreeta or modular al product o good to resort to a power supply external. The type of ceiling lampcion, physical dimensions and total power requiredwound will constitute the criteria for selectedción. Although both options are viables, a power supply external usually offers more flexibledad, especially if he productor is it going to be used worldwide. However, so good it may seem like a choice prudent, selection of the wrong external source may affect the reliability of the productor that feed. This can not only cause discomfort and be frustratesnte for customers, but in the long term it can damage the brand image and reputation of the manufacturer of the producto.
Criteria thisciales
Engineering requirements state the voltage and current that accurate el producteither; These are the initial criteria from which selectedconnect the power supply. In most cases, andl product will need a single input DC voltage, for example 12 VCC, and connect to the AC mains. The maximum current required by the product should include all peripherals attachedados o that enginees what do you knowegive use and are fed by the productor during use. Por example, si the maximum current required is 2 A, the total power output of the power supply will be 24 W. The power supply must take into account the output power at maximum load and ha to function reliably, continuouslyoh without overheating. Al selectedconnect a power source external for these parameters, the engineer will encounter other factors to take into account that will increase the degree of completequality of the process selectedción.
Broadly speaking, these factors can be classified into three categorydays: mecsmithereens,éctricos, and security standards as well as their compliance.
Guysmithereens
dependedend of the required power, you may be able to choose between a power supply external desktop type or plug-in type to the wall that connects directmind to la plug. The sources or wall plug-in power adapters typically provide output power on the order of 3 W a 45W, They are practical and small in size. The output may be connected director, for tensions andstáwalk as the output USB de 5 VCC, se supplied by ato power outlet andstágo. If the outlet is wired, the length will be enough to reach the productor in most of the uses that are I'm going to give him? Also, what type of DC outlet is provided for the productor, and is available for the selected socket? The manufacturer's data sheet should show thethe pegs of CC available, They use to be type estáwalk (rectumaI'm in right angle), the power connector USB y el Connector EIAJ.
Is there a lock option available or the outlet is customized, and if so, the manufacturer can connect the plug correspondedbeing or onsupply bare output cable y tinned? Don't forgetidbe sure to check the polardad of the plug, where the socket will sit inside the socket. producto and how it will hold. The AC input of a wall adapter also offers several opciones. First, if the product is to be used worldwide, the availability of configurations interchangeplug changeable, either two or three pins, facilitate encapsulation producto. The ground/ground pin of a wall adapter is not normally used and the DC output flota respector ground; This type of source is called Clase II. The website of the IEC provides practical information on the different types of plugs. The input AC voltage range must also be confirmed., although most of the sources wall and tabletop supplied by that manufacturers renowned offer the universal AC voltage range of 90 a 264 BCA y 50/60Hz.
Figurea 1 - Commonly available DC pins for a power supply external of sobremesa (Source: CUI)
Desktop power supplies typically offer a set of mechanical options similarIt is for the input and output connector.. Desktop sources do not usually have physical limitations like their wall-mounted counterparts, so they usually offer a power of up to 250W, such as series SDI250-U de IN. The input will generally be a standard jack/socket IEC320/C14, but it is necessary to verify that there isa power cords available for all types of plugs in different countries and regiones where you can use the producto. Depending on the higher power output and de the need to supply optional power cords for a certain country, desktop power supplies can add size and weight considerations to the packaging criteria of the producto.
The construction mecáExperience of the power supply will also influence the application environment of the producto, in which environmental conditions, among others, are cruciales. Between these factores may be moisture ingress and temperature de work, which are considered later in the section dedicated to the estáwalkes.
A final note on possible ways customizing power supply. We all know the black plastic structure used in power supplies. externals, but the design of the productos has been getting more and more refined and painstaking, even at the level of Customizedlove. You have to think about how the power supply will fit with the aesthetics of the producto. Is posible print your company logo or brand on the case, Does the adapter have the colors of your company and even a special package? From the point of view of consumgoner, small details like these offer a very favorable effect on the aspects visualIt is from your general experience when opening the packaging of the productor for the first time.
Especifications andlécitric
In addition to input voltage, current and frequency, already mentionedas, it is necessary to check some electrical parameters of character crítico. From the input point of view, the supply inrush current must appear in the technical data sheet, that is, the peak current instantánea at “cold start”, who can cause trip innceasecustomer line breaker io. It is also important to check that the leakage current is within the especificcionis (see set apart from isáwalkes). DC output requires close inspection; la regulatescion of load, the ripple and noise are críticos. Can the power supply mantener output voltage within a range acceptable for all load conditions and all ranges of input AC voltage? A Reguulatetion of the + / - 5% is usually adequate, which means maintaining an output of 5 V rated in the range of 4,75 - 5,5 VCC. Also, does the operation of the power supply need a minimum load? Ripple and noise are criteria especially importantis for sensitive semiconductor devices like FPGA y micro controlworshipers, and a high noise level may require Add components de filtrI love inside your product in order of achieve reliable operation. Por andexample, the 5 VDC source SDM36-U of CUI is characterized by a maximum level of ripple and noise of 80mV pp.
Figurea 2 - This graph indicates the regulatestion for differentis load conditions and input voltage (Source:CUI)
Figurea 3 - Evolution of efficiency standards energyethics in the world
(Source: IN)
La Figurea 4 shows the average efficiency minimum y the maximum no-load consumption for a single power supply with a low output voltage. By compareation, el European Ecodesign (2019/1782) also includes a low charge that requires the manufacturer to provide the efficiency for the 10% of the established maximum load.
Figurea 4 - Requirements of DoE Level VI for AC/DC power supplies externals (Source: CUI)
Recent advances in semiconductor process technologies used in switching transistors dand power converters improve the efficiencyia, veterann the weight and decrease the size of power supplies outside. E.g., the external desktop source SDI220G-U of CUI uses gallium nitride semiconductors (GaN) de great band gap to increase efficiency up to 96 %, reducego weight a 32% and decrease the overall size by more than half if compareto previous models.
In addition to the aforementioned requirements on safety and efficiency energyethics, power supplies also need to meet thes compatibility standards electromagnetética for noise I am drivinggone and radiated, among which the most cited are FCC 20870, CISPR22 e IEC 61204-3. It is also worth noting that for medical applications, the 3rd edition of IEC -1 incorpora immunity criteria electromagnetéticthat are detailed in the standard IEC 60601 1 2 which is in your 4ª edición.
Conclusionón
adapters External current AC/DC desktop and plug-in to the wall offer a convenient way to power a wide variety of dand consumeo, sanitary and industrials. In addition to the requirements blowingcialis voltage and current, as well as its conventional appearance, engineers must provide Atención to the not-so-obvious specifications of the Customizedador by carefully reading the technical data sheet of the adapter and making sure they fit equippedor to the requirements of the producto. power adapters andexternal may experience variationsignificatesize vats, weight and coste, despite apparently having some values similares.
