SD card standards. What is a UHS SD card and what is the difference between UHS-I, UHS-II and UHS-III? Selecting an SD card
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Most often, mobile device owners do not have enough built-in memory to store information. Knowing that what is an sd card on android and how to use it, we can significantly expand the amount of existing memory and, accordingly, the capabilities of our phone.
SD card on Android: what is it and how to choose it?
Even the most inexperienced user usually installs many applications on his device. To save space, it is recommended to transfer them to an SD card.
Secure digital card, or SD card, is a special memory card format that is used on portable devices. These can be smartphones, cameras, PDAs, e-books, navigators, etc. Today this format of memory cards is the most popular and very widespread.
The predecessor of the SD card is considered to be the MMC. It has the same parameters, but the Secure digital card provides information protection (both from erasure by the user himself and from unauthorized copying).
So, we found out what an SD card is on Android. How to choose such a card? First of all, we should definitely make sure that this is the format we need. In this case, it will not be superfluous to read the instructions for your mobile device. It is also advisable to find out which speed class is suitable for our phone. This is especially important for cards with large amounts of memory. The price of an SD card directly depends on the capacity and speed class. Some manufacturers also provide a warranty on their memory cards (1-5 years on average).
How to install an Android application on an SD card?
All our programs remain on the built-in memory of the mobile device. Unfortunately, usually the capacity of such memory is quickly exhausted, and therefore a memory card can significantly expand our information storage capabilities.
Developers Android versions 2.2 managed to provide for this. Owners of such devices can install programs on an SD card using standard means. To do this, go to the “Applications” menu through the phone settings and select “Manage applications”. From there we can transfer programs to the memory card.
However, what if we have installed version up to 2.1 inclusive? The main way to correct the situation is to root your phone, after backing up all the information on the card. It is highly not recommended for inexperienced users to do this.
After this, you will need to split the SD card into several sections using special software (for example, MiniTool Partition Wizard). Next we connect mobile device to PC, launch installed program and delete all sections from the map.
The next step is to create a large user partition, Primary FAT32, where our information will be stored, and a 2nd partition, Primary ext2. Now everything that was stored on the memory card can be transferred back (if we have previously performed a back-up). We reboot the device and begin installing Link2SD, thanks to which we can install programs on the SD card. Reboot again and allow root access. A request will appear where we need ext2.
We reboot our device again. Now you can click the “Create link” button and transfer the necessary programs.
How to understand the class of a card, what UHS is and how to choose the best card at the lowest price.
We will tell you everything using examples of Toshiba SD cards. All data is relevant for CF and other types of cards.
The card always indicates the card type, data transfer speed, card class and bus.
Types of cards
There are three types of SD cards:
- SD- the very first memory cards, compatible with all devices. Capacity up to 2 GB.
- SDHC - SD High Capacity— cards with increased capacity. Capacity 4 - 32 GB.
- SDXC - SD Extended Capacity— extended capacity cards. Capacity 32 GB - 4 TB.
Speed
For photography, the recording speed at which the camera will save data is important.
On cards, the speed may be indicated directly, for example 95 Mb/s.
You can also find cards in which the operating speed is indicated in multiples, for example 600x. The multiplicity is always the same x=150 kb/s.
100x = 100 x 0.15 kbps = 15 Mbps. This speed went back to CD-ROMs (things that existed before the iPod and long before the iPhone). The maximum multiple speed is 633x (95 MB/s). For CF cards, the maximum speed multiple is 1066x (160 MB/s).
For example, Toshiba EXCERIA PRO UHS-II 16GB. Read and write speeds are 260 and 240 MB/s, respectively. This means that a gigabyte of data will be written to the card in 4 seconds. The main thing is that your camera supports this speed and bus (you will learn about it below).
Card class
The card class specifies the minimum guaranteed streaming write speed. For example, Class 10 corresponds to a speed of 10 Mb/s.
For video, it is not the peak speed that is important, but the streaming recording speed, otherwise there will be frame loss.
Since 2009, additional classes U1 and U3 have been introduced for SD cards (based on the new high-speed UHS bus). The classes provide a minimum speed of 10 and 30 Mb/s, respectively.
Example. Toshiba EXCERIA UHS-I. The card uses UHS speed class 3, which provides a minimum speed of 30 Mb/s. and although its maximum write and read speeds are 60 and 95 MB/s, this card is capable of recording video at 4K resolution.
Below is a table of correspondence between class and minimum streaming recording speed.
SD recently developed new standards for card classes that will allow you to shoot video in 8K resolution.
What is UHS
UHS - (Ultra High Speed) ultra-high-speed bus that provides maximum recording speed.
- UHS-I supports speeds up to 104 MB/s
- UHS-II supports up to 312 Mb/s.
UHS-II cards can be identified by two rows of contacts.
Example
As you can see, the speed indicated here is 260 Mb/s. Roman I means UHS-I class. And U3 shows that the card supports 4K video shooting.
Which card to choose
- Shooting FullHD video using Class 10 cards or Class U1 cards from the EXCERIA series.
- Maximum Photo Recording Speed – Choose the fastest speed UHS-II cards from the EXCERIA PRO series.
- Shooting 4K video using U3 class cards from the EXCERIA series.
- High recording speed + 4K video shooting - U3 class cards and UHS-II bus of the EXCERIA PRO series.
Welcome to my blog!
The SD card has become so popular that it is already difficult to find a digital device that does not support one of the types of this flash drive. They are used in cameras, phones, tablets, and video recorders. Laptops and netbooks have slots for connecting them, and such a flash drive can be connected to a computer via a special adapter.
The large number of types of such flash drives sometimes makes it difficult right choice and you have to delve into the intricacies of their characteristics in order to choose exactly the model that you need.
After reading this article, you will learn how to choose a memory card and what parameters you need to pay attention to when purchasing it.
The SD card format was developed in 1999, with companies such as SanDisk, Panasonic and Toshiba taking part in the development. The MMC card, popular at that time, was taken as a basis.
In 2000, the non-profit organization SD Card Association was created by companies such as Toshiba, SanDisk and Matsushita, which established a single standard for all types of memory cards.
The main parameters by which you need to choose such a flash drive are its size, memory capacity and writing speed. The secondary ones are the manufacturer and its price, which can vary greatly at different retail outlets.
SD card size.
The first thing you need to pay attention to when choosing a flash drive is its size, or rather, what size you need. There are currently three sizes of SD cards - SD, miniSD and microSD.
SD cards are the most large cards memories from this family are used in digital video cameras and cameras, navigators, as well as other equipment. Many laptops and netbooks are equipped with a slot for such a flash drive, which is very convenient when transferring photos and videos from a camera to a laptop.
MiniSD cards are slightly smaller in size than SD cards and were developed for use in cell phones. Currently, they are practically not used; they are difficult to find on sale.
MicroSD are the smallest memory cards from this family. They are very widely used in modern equipment, smartphones, tablets, video recorders and other miniature equipment.
When choosing a flash drive, decide on its size; if your gadget uses the SD format, then take an SD card and adapters; it’s better not to use it unless absolutely necessary.
Types of SD cards.
An important parameter of modern flash drives is their type, and if your equipment supports an old type of card, then it may not recognize newer types of drives.
The table shows the main types of flash drives.
| SD 1.0 | Supports memory capacity from 8 MB to 2 GB |
| SD 1.1 | Supports memory capacity up to 4 GB |
| SDHC | supports memory capacity up to 32 GB |
| SDXC | Supports memory capacity up to 2 TB |
All modern flash drives are produced in SDHC and SDXC standards; ordinary SD cards are already very difficult to find on sale.
SD 1.0 and SD 1.1 – Secure Digital, the very first types of flash drives that are no longer used in modern devices. Models of this type had byte addressing, similar to addressing random access memory, which prevented them from increasing the memory beyond 2 GB for version 1.0 and 4 GB for version 1.1. If you have an old gadget that supports no more than 2 GB of memory, then you need to look for the SD 1.0 option for it, and not SD 1.1.
SDHC – Secure Digital High Capacity, these flash memory cards will no longer work on devices that were designed only for SD type. This is due to the fact that such cards have sector-by-sector addressing, which can be compared to that used in hard drives, thanks to which it was possible to increase the memory capacity of such cards.
SDXC – Secure Digital eXtended Capacity, this is the most modern type flash memory cards, which in turn is divided into SDXC UHS-I and SDXC UHS-II versions.
SDXC UHS-I – memory cards of this type can be connected to SDHC devices.
SDXC UHS-II – cards of this type are not compatible with SDHC devices.
Cards SDXC memory were created specifically for digital SLR cameras and camcorders to record high-quality video in 4k format and take photos in RAW format.
SDXC UHS-II cards are best suited for these purposes.
SDHC memory cards are supported by almost all modern devices, but you need to check the device's support for SDXC memory cards in the user manual.
You can find out what type of memory card it is by looking at its labeling; all high-quality drives have corresponding labels.
Over time, memory cards are constantly being improved, and what type of flash drive your device supports, check in the operating instructions or on the website of the manufacturer of your device.
And of course, we can’t help but mention flash drives with a WI-FI module, which expand their capabilities. When you connect such a card to a device, it automatically has a Wi-Fi module.
Using such cards, you can easily transfer images from your camera to your computer without using any cords or removing the card from the device.
You can find out about the support of memory cards with a Wi-Fi module by your device in the user manual.
SD card classes.
The class of an SD card determines its writing speed and the higher it is, the faster the flash drive works. Total for this moment There are 6 main classes into which all flash drives are divided and several additional ones that appear with increasing write speed.
The speed of such flash drives is determined in the same way as for CD-ROM drives, that is, the speed of 1x is equal to 150 KB / s, the first speed of the CD-ROM drive. The slowest flash drives have a speed of 13x or 1950KB/s, but it is not convenient to indicate it in kilobytes, so it is customary to indicate it in megabytes.
The table shows the six main classes and their minimum write speed.
What class the memory card corresponds to is indicated on its labeling.
As I already said, in addition to the main classes, there are also additional ones, which are immediately designated by recording speed or multipliers, for example 200x, 400x, 600x, etc.
To quickly find out the minimum write speed of such a card, you need to multiply the number written on it by 0.15.
So a drive labeled 200x has a minimum write speed of 30 MB/s, and a drive labeled 600x has a minimum write speed of 90 MB/s.
So what class card should you buy?
If you look at the numbers, a class 6 flash drive is quite enough to easily record video in Full HD format, but in practice, few people look at the test results.
Let's say you need such a card as an external drive, then you can safely take it in class 6, its speed is quite enough to quickly write files, and such cards are a little cheaper than fast ones.
If you need a card for a DVR, smartphone or tablet, then take grade 10, especially if you plan to record video often. This is not because a class 6 card will not cope with this task, it just makes no sense to take a lower class for almost the same money.
Well, if you have a modern digital camera or video camera, then it’s better to buy the fastest card that it supports; how quickly you can take several pictures in a row and not miss the desired frame while the clipboard is freeing up can play a role here.
The memory capacity of this flash drive is constantly increasing, but what the user needs to know when choosing such a card is the maximum amount of memory that his device supports so that the purchase is not in vain.
At the time of writing, the largest SD card has a capacity of 512 GB, but not every device will be able to work with such a card.
If you use it as an external drive, then there will be no problems with large-capacity cards, but if you use it as a drive for a digital device, such as a DVR, player or tablet, then there may be compatibility problems.
Most older gadgets support flash drives up to 32 GB, this figure increases over time, but be sure to check the user manual for your device.
File system of the memory card.
When purchasing a flash drive, the user must know what file system it supports in order to avoid compatibility problems between the card and the gadget.
All SD and SDHC format drives are formatted in FAT32 by default and this file system is supported by all devices that use memory cards. The downside of this system is that it does not support volumes larger than 4 GB, which can be a problem when writing large files.
New SDXC memory cards support the new exFAT file system, in which such restrictions on file size are removed, but the problem is that older devices do not see this format and you cannot use such a card with them.
The advantage of the exFAT format is that the number of records per cell is reduced compared to FAT32, which will have a positive effect on the service life of such a card.
If you want to use a memory card as an external drive, you can easily format it in NTFS format and work with it as with a simple local drive.
If you wish, you can disable writing files to your SD card so that an unauthorized user cannot write anything to it without your knowledge.
This is very simple to do, you need to lower the lock switch all the way down, and then insert the memory card into the device and writing to it will not be possible if the device itself supports such a function.
If you use miniSD card or microSD, then such a lock is on the adapters for these cards.
When you insert such a drive into the device and look at its properties, you will see that the “Create” item is no longer in the menu and you will not be able to create any file on it. If the device does not have such a slot, or it is of the wrong format, then a memory card can be connected using an adapter or card reader that connects to a USB port.
Using such adapters, you can connect a flash drive of any format to your gadget or laptop.
If it is not possible to connect a memory card directly or through a standard adapter, then you can use an adapter for a microSD card, which connects to the USB port of the device. Using such adapters, for example, I connected a memory card to my tablet.
The disadvantage of such adapters is their poor reliability; if you take cheap options, they quickly break, but they also cost a penny.
There are also universal card readers with which you can connect all popular flash drives to your computer. There are options for both internal connection of a card reader and external connection via a USB port.
Manufacturer of flash drives.
SD memory cards are produced by many companies that produce and, these are companies such as Transcend, SanDisk, Kingston, Samsung, SmartBuy, which are very popular.
Personally, from these companies, I use the products of Transcend, SanDisk, Kingston, if I need to get a better card, and SmartBuy, if it’s cheaper.
In my practice, there have been several cases of microSD cards failing, so it is better not to store on them important information, which you are afraid of losing, regularly copy it to a reliable source.
Now you know what an SD card is and how to choose a memory card.
Good luck!
Modern flagship and even budget phones are equipped with large built-in memory. They can even have 8-16 GB of memory (and flagship smartphones have all 128 GB), and this does not include a flash drive. However, for many users this is not enough. However, there is a good solution - choose a memory card for your smartphone. Which one is another question. To make the right choice, you need to know what cards are available, how fast they work, etc.
What is it for?
A memory card is designed to expand data storage space. If music, photos or videos do not fit on the phone’s “native” memory, then it is appropriate to think about which memory card to choose for your smartphone. Most phones have special connectors for connecting such cards. All of them support the MicroSD format. Cards of this format are compact and most efficiently built into the case itself, which is why they take up little space. Certain models use universal slots into which you can insert either a SIM card or a flash drive.
So users can choose: either expand the memory, or use two memory cards at once. Smartphones with this solution are most often budget ones. Before choosing a card, you need to find out whether your phone supports the required types of flash drives. This is indicated in the technical specifications for the phone and on the manufacturer’s website. Also on the case, in the area of the flash drive slot, the format for the card that can be used is indicated.
Memory types
When choosing the best memory card for your smartphone, the first thing you need to consider is the type. There are only 3 standards:
- MicroSD - the capacity of these cards does not exceed 4 GB.
- MicroSDHC - up to 32 GB.
- MicroSDXC - up to 2 TB.
The latter type of card can be inserted into a standard MicroSD slot, but it must be supported operating system. Therefore, when choosing such a drive, you must check whether the phone’s OS supports memory cards of this standard. Most often, drives of this type are supported by flagship phone models; budget phones are limited to the MicroSDHC standard.
Recording speed and class
The higher the card class, the faster the data exchange between devices (writing and reading files). Currently there are cards with three recording classes:
- Speed Class (letter C). Write speed can vary from 2 to 10 MB/s.
- UHS Speed Class (U). Speed from 10 to 30 MB/s.
- Video Speed Class (V) - from 6 to 90 MB/s.
The final speed depends on the class. For example, a Class 10 memory card (Video Speed Class 10) has a write speed of 10 MB/s or more. Such flash drives are used for recording videos in FullHD format, as well as for streaming.
Volume
Modern drives can have a capacity from one gigabyte to two terabytes (2000 GB). Of course, the price of memory cards greatly depends on the capacity. However, when choosing, it is worth considering that phones have limitations on the volume of storage devices that can be connected to them. Many budget smartphones are designed to connect a card up to 16 GB. Therefore, they will not be able to work with a 32 GB drive. Hence the misunderstanding among people whose smartphones do not see memory cards. The specifications must indicate what size card the phone can work with. And if you install a 32 GB flash drive into a phone that only supports 16 GB, it simply won’t recognize it.
Manufacturers
There are many second-rate manufacturers who offer their products in the market. However, the majority are occupied by well-known and well-established companies:
- SanDisk.
- Kingston.
- Transcend.
Silicon Power products enter the market quite confidently, offering users inexpensive, but sufficiently good solutions. When talking about which memory card to choose for a smartphone, we can first recommend the four manufacturers mentioned above.
File system
Most flash drives are formatted in the FAT32 file system. It has the disadvantage of not supporting volume sizes larger than four gigabytes. This means that trying to record a movie of at least 4.5 GB in size onto a flash drive will not work. The maximum file size cannot exceed 4 GB, which is bad because it imposes a number of restrictions on users.
Another drive file system is exFAT, and there is no such limitation. However, the device itself must support a similar file system in order to be able to read a flash drive of this format. Otherwise, you will encounter a situation where the smartphone does not see the memory card. This is also required in the specifications for the phone.
Durability
All information on media cannot be stored forever, since they have a certain service life. On average, the media resource is 10,000-1,000,000 rewrite cycles, although in practice the figure is lower. In general, the longevity of a MicroSD drive depends on its use and assembly. Models from unknown brands are not subject to strict control during production, so they may break after 2-3 weeks of use. Therefore, if you don’t know which memory card to choose for your smartphone, then it’s better to give preference to a well-known manufacturer, even if the price is a little higher.
Rating of the best
Considering the fact that almost all phones can shoot video in FullHD format, you need to choose a class 10 memory card. The best are the following:
- ADATA Premier (volume available in the range of 8-128 GB).
- Transcend MicroSDHC (8-256 GB).
- SanDisk Extreme (16-128 GB).
- SanDisk Extreme Pro (64-128 GB).
- SanDisk Ultra (8-128 GB).
- Memory cards for smartphone "Samsung EVO" (16-128 GB).
The cards mentioned above have an almost ideal price-quality ratio, they satisfy customer requests, collect positive reviews, work great and allow you not only to save photos, but to quickly record video in FullHD format.
ADATA Premier
The price of an ADATA Premier memory card will be 500 rubles for the 16 GB version. Flash drives in this series have a good price at high quality, are reliable and durable, perform well when recording video in resolutions up to FullHD.
In general, this line includes memory cards with a capacity of up to 128 GB, but their price is higher. And they are only suitable for those users who store a lot of data on their phone.
- Protection.
- Reliability.
- Lifetime warranty on the card from the manufacturer.
- High recording speed.
Flaws:
- The line is limited in terms of memory capacity.
- Higher price compared to similar drives.
Transcend MicroSDHC
For 400 rubles you can purchase a model with a memory capacity of 16 GB. Its characteristics correspond to the previous memory card in the rating; it has a high data exchange speed. However, the entire line has a capacity limitation of 256 GB. In general, Transcend has long established itself as a reliable manufacturer of high-quality devices, so there should be no problems with their flash drives.
Advantages:
- Reliability.
- High recording speed.
- Lifetime warranty.
SanDisk Extreme
The cost of this card is 2100 rubles, and this is for a model with a memory capacity of only 32 GB. A very expensive, but also durable card, different from standard models. It is shockproof, waterproof, and X-ray resistant. It is suitable for use in extreme conditions. The maximum capacity of a card in this line is 128 GB.
The price is the main disadvantage of this model. However specifications completely justify the high price.
- Lifetime warranty.
- Write speed.
- Can be used under any conditions.
- High price.
There is also a more advanced version of this card - SanDisk Extreme Pro. It differs from the previous one (without the Pro console) by a higher recording speed, which allows you to record video in best quality and faster. But the fact is that the entire line is represented by only two models - with a capacity of 64 and 128 GB. Few users want to purchase it. Most often, such protection as a flash drive has is simply not necessary.
SanDisk Ultra
For just 350 rubles you can buy an inexpensive and good flash drive for your smartphone. It has classic characteristics, a low price, and the manufacturer is reliable and well-known. Given its parameters, the flash drive is cheaper than other models, and the model range includes cards with different memory capacities, so there is plenty to choose from.
Samsung EVO
These cards from Samsung cost an average of 500 rubles (price for the version with 16 GB of memory), they are water and thermal protection, and are also protected from magnetic fields and X-ray radiation. At the same time, the exchange speed is quite high. As for the price, it is slightly higher than the cost of similar models, but the price tag is due to the presence of protection.
Silicon Power
For a flash drive with 8 GB memory from Silicon Power you will have to pay 550 rubles. It's expensive for such a volume. In addition, the flash drive belongs to class 4, so the writing speed will be low. However, it is not intended for recording FullHD video; it is better to save photos and audio files on it.
Pros - durability. The memory card is actively used in phones that do not require high technical requirements. The disadvantage is the price. Given its characteristics (low recording speed, small volume), the cost of 550 rubles seems unfair. Therefore, models from Silicon Power can be recommended last. When choosing, you first need to consider models from manufacturers that are higher in this rating.
Conclusion
As a conclusion, you can answer common questions. In particular, many users want to know whether it is possible to buy cheap memory cards. In principle, it is possible, but it is advisable to store on them only information that you do not mind losing. The risk is large, so it is advisable to “dump” important documents in parallel onto other media.
It is also completely unnecessary to look for a class 10 memory card in order to insert it into an inexpensive smartphone. If the phone cannot shoot video in FullHD resolution, then a regular class 4 memory card is enough for it. As for the size of the card, everything is individual. Many users do not need a flash drive at all, since the built-in memory is enough for them. For others, even 128 GB of memory is not enough due to the large number of stored photos, music and video files. But in any case, when choosing a card, you need to take into account what maximum volume the smartphone supports. There's no point in trying to cram a 32GB card into a phone if it only supports a maximum of 16GB.
And one last thing. Almost all smartphones with a memory card slot support drives from all manufacturers. It does not happen that, for example, Samsung brand phones only support cards from Samsung.