What R, C values to use in an RC Snubber to reduce output ringing in switching regulator?

A

Adam B

I am using a simple buck switching converter (AP3211) to convert 5V-12V to 3.3V.

The issue I am trying to resolve is the output ringing. I see a 800mV P-P ringing on the output, with a frequency of 185MHz. I've read details that I could possibly use an RC snubber to reduce the ringing.

Some references I found:

http://www.ti.com/lit/an/slyt465/slyt465.pdf

onsemi.com/pub_link/Collateral/TND396-D.PDF

The schottky diode has a Junction Capacitance of 120pF. A few different articles have a slightly different approach to calculate the R and C values for the snubber, however I've come to the following values:

R = 7 Ohm C = 270 pF

My question is: If I don't care about power consumption (to an extent, and not enough to use a linear regulator), could I use lower R and higher C to reduce the ringing even further? If so, what are suitable values for R and C?

Schematic showing RC snubber in RED
 

Unreplied Threads

Problemas con mi editor VSCode (Creo que es el scriptcs pero no encuentro solucion)

hace un tiempo he venido programando en VisualCode pero cuando intento correr el codigo en mi editor me da un error en la pestaña Output, el error es el siguiente: [Running] scriptcs "c:\Users\juand\Desktop\C#\Program.cs" "scriptcs" no se reconoce como un comando interno o externo, programa o archivo por lotes ejecutable.

[Done] exited with code=1 in 2.002 seconds

tengo la carpeta de scriptcs en la misma carpeta donde estoy haciendo mi proyecto y ya he intentado solucionarlo agregandola al path y una infinidad de cosas diferentes pero nada me ayuda co eso, si alguien podria ayudarme se lo agradeceria mucho.

How to design a flex PCB with 4 I2C sensors?

  • omen08776
  • Physics
  • Replies: 0
I am trying to design a 4 direction TOF array with a single I2C bus. The implementation will be on a flex PCB with the sensors being mounted on stiffeners.

Sensor : VL53L1

I will use the XSHUT pin on each of the sensors to write an unique address using an ESP32C3 each time the system is powered up. TUTORIAL

The pinout of the PCB end would be - 3.3V, SCL, SDA, XSHUT1-4, GND.

enter image description here

What are the PCB design requirements in such a design ? Will I have to add pull up resistors on each of the sensors for all the pins? (Except 3v3 and GND). The length of the PCB will be at max 25cm.

Nandland Go Board - Diamond Programmer

  • vigilante_fresh
  • Physics
  • Replies: 0
I'm trying to program my first FPGA with the Nandland Go Board on Windows 11.

I've followed all the instructions in these tutorial videos:


But I'm getting stuck at the very last step, when clicking the "Program" button in Diamond Programmer. Here's a screenshot of the error I keep getting:

enter image description here

I followed the instructions in the error and read the suggested help topic. Still not working.

One thing worth noting is that in the tutorial video, he has the option to choose either FTUSB-1 or FTUSB-0 for his port. On my laptop I'm only getting the option for FTUSB-0. Not sure if that's related.

Deals: refurbished iPhone 15 models, Galaxy S24 series discounts and foldables

  • GSMArena.com - Latest articles
  • Android
  • Replies: 0

Deals: refurbished iPhone 15 models, Galaxy S24 series discounts and foldables​


Peter 15 September 2024

Deals


This week all eyes were on Apple and the new iPhone 16 series. Pre-orders started this Friday and will last a week – shipments and open sales start next Friday.

You can pre-order from Apple.com and, if you do, make sure to check the trade-in deals. Apple made a big deal about them during the presentation. Here are the US prices for the four iPhone 16 models without trade-in (they cost the same as last year’s 15-series).

iPhone 16iPhone 16 PlusiPhone 16 ProiPhone 16 Pro Max
US$799$899$999$1,199

Are you getting an iPhone 16? While you ponder that, here are some alternatives. The obvious place to start is other iPhones, so we looked at some refurbished units from Amazon. In part because they are cheaper, but also because you can’t buy new iPhone 15 Pro or 15 Pro Max from Apple anymore (but Apple.com still stocks new 15 and 15 Plus).

The iPhone 16 and 16 Plus kept the same 6.1” and 6.7” screens as their 15-series counterparts. Yes, they still have 60Hz panels. So, what changed? The more powerful Apple A18 chipset and the extra RAM allow the 16-series phones to run Apple Intelligence, the 15 and 15 Plus will not be supported. The new models also have faster charging and new ultra wide cameras with macro mode. Perhaps the biggest upgrade is the Camera Control and the Action Button, which enable a host of new shortcuts.

But looking back at the iPhone 15 and 15 Plus, they have the same screens. The same 48MP main cameras and 12MP selfie cameras too.

The iPhone 16 Pro and 16 Pro Max get larger 6.3” and 6.9” displays. That’s good for those who like large displays, but bad for those who think that the new models are too big. The faster charging and new buttons are also present on the 16 Pro duo. Also, there is a new 48MP ultra wide camera and this year, the small Pro has the same 5x periscope as the Pro Max (the 15 Pro has a 3x lens).

Unlike the vanilla models, the iPhone 15 Pro and 15 Pro Max will be updated with Apple Intelligence (coming next month). The main and selfie cameras are the same and the 15 Pro Max even has the same periscope.

You can switch to Android this generation. All Galaxy S24 models have 120Hz LTPO displays and they all have AI (mostly powered by Google).

The Samsung Galaxy S24 Ultra has both a 5x periscope (with a 50MP sensor to boot, not 12MP like on the iPhones) and there is also a 3x lens. The main camera has a 200MP sensor. There is the S Pen too, which gives this phone tablet-like skills.


The Samsung Galaxy S24+ has a 6.7” display, the same size as the iPhone 15 Plus and 16 Plus. But as we noted above, instead of an outdated 60Hz panel you get a 120Hz LTPO panel. This model also has a telephoto camera (3x 10MP).

The new iPhone 16 Pro is larger than the Galaxy S24. And with no new Xperia 5 this year and no small Zenfone 11 in sight, these are the last small flagships standing. The small S24 also has a 120Hz LTPO display a 3x 10MP tele camera, things for which Apple charges extra.


Apple still has no foldables, so there is no direct competitor for the Galaxy Z Fold6. But we couldn’t pass it over after we saw the $400 discount. It’s still expensive, but maybe now is the time to switch to a foldable.

Flip foldables probably make a better alternative to iPhones and there are plenty to choose from. Starting with the Galaxy Z Flip6, which can be yours for $950, which is less than a new iPhone 16 Pro (note: we have linked the 512GB Z Flip6 as the 256GB model had a smaller discount, so both ended up costing the same).

Then there are the Motorola razrs. These range from quite cheap – the razr 2023 is just $400, which is mid-ranger money (and to be fair, it is a mid-ranger) – to not so expensive with the razr+ 2024 at $900. If you’re not sure which one is right for you, we’d recommend the razr+ 2023 – it’s priced well (at $600 it is $100 less than the razr 2024) while still offering good performance (Snapdragon 8+ Gen 1) and a large, functional cover display (3.6”, 144Hz).

That’s it for foldables and we have one more phone to offer – the Motorola Edge (2024). It’s $450, but the curved 6.6” 144Hz OLED display and vegan leather back give it a premium look. It has a 50MP main camera and a 13MP ultra wide on its back. The 5,000mAh battery supports fast 68W wired and 15W wireless charging. The Snapdragon 7s Gen 2 chipset is pretty slow for this price range, but the phone does have Ready For (Moto’s desktop environment).

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Какие контролы использовать в WinForms для открытия в одном окне нескольких текстовых документов?

Давно сидит в голове идея программы для анализа кода (практически с самого начала изучения c#), но в силу недостатка опыта работы с WinForms и дизайнером не могу придумать, какие контролы использовать для этого. Общая идея выглядит примерно так:

  1. Предполагается, что программа будет выполнять поиск в выбранной области на диске (папка проекта) и открывать все файлы с расширением *.cs.
  2. Открываться они будут в виде "плиток", внутри каждой будет код соответствующего файла.
  3. Планируется, чтобы плитки возможно было перетаскивать в произвольное место в окне, при этом если они не мешают соседним, то смогут оставаться в выбранном месте, если же плитка будет помещена поверх соседней, то будет автоматически корректировать свое расположение.
  4. Плитки можно перетаскивать группами, выделив нужные.
  5. Должна быть доступна функция "масштабирования" - пропорциональное увеличение или уменьшение масштаба прокруткой колеса мышки (от общего вида всех плиток, до степени, позволяющей свободно читать код), с центром в точке расположения курсора мышки (как на гугл карте), а также смещения вида перетаскиванием за незанятую область.

Итого. В программе условно-бесконечный "холст", способный вместить любое количество плиток, и их можно свободно таскать по нему, а также смещать сам холст и масштабировать вид. Это только то, что относится к представлению, самое интересное (если получится) будет в функциях анализа кода.

Возможно ли реализовать это на WinForms? Если да - подскажите, какие контролы для этого подойдут. Заранее спасибо! P.S. На скрине изобразил, как это примерно может выглядеть. Пример

Как в smtp phpmailer вывести текст из БД ссылкой?

  • Сергей Краснодарский
  • Technology
  • Replies: 0
подскажите пожалуйста как в письме smtp phpmailer вставить ссылку из БД? в старом коде mail php было так $arr[$rr['email']] .= 'N '.$rr['id'].' - <a href="'.$base.'tema/'.$rr['zag_url'].'_'.$rr['id'].'">'.$rr['zag'].'</a><br>'; Сейчас " емаил" и " N " я вывел это нормально отображается и в ссылке они не нужны {$row["email"]} {$row["id"]} Отдельно отображается и $base просто выводит главную страницу сайта, zag_url то же коректно отображается, а как вывести всё вместе -

Code: 
<a href="'.$base.'tema/'.$row['zag_url'].'_'.$row['id'].'">'</a> ');

всё какие то ошибки выдаёт, в интернете то же примеров подобных не нахожу.

Асинхронная запись в файл (c#)

Занимаюсь написанием ТГ-бота, есть асинхронный метод, который обрабатывает сообщения пользователей и, если пользователь зашел в бота впервые, записывает данные его ТГ-аккаунта в .json файл.

Подозреваю, что возможен случай одновременного обращения к файлу при одновременном обращении новых пользователей в бота, соответственно два потока будут пытаться писать в один файл

Подскажите как можно исключить данную ситуацию?

Code: 
  public static async Task UpdateUserFile(string jsonPath, List<User> userList)
    {
        try
        {
            var jsonString = System.Text.Json.JsonSerializer.Serialize(userList);
            await System.IO.File.WriteAllTextAsync(jsonPath, jsonString);
        }
        catch (Exception ex)
        {
            ///...
        }
    }
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