Choosing the right memory card for your application can be the difference between success and failure. Size, format, read/write speeds, storage capacity, operating environment, reliability, performance, longevity, brand and price, are all considerations.
One of the most important factors has to be performance, or if you like speed: the speed at which data can be both written and read. Speed is very important if you’re in the business of data capture or data recording.
Your chosen memory solution needs to be able to keep pace with the volume of data being generated by your device/application, and/or your device’s appetite to access the data stored on a memory card.
When it comes to performance, there are a number of Speed Classes to be aware of:
- Speed Class
- UHS Speed Class
- Video Speed Class
- Application Performance Class
SPEED CLASS (often referred to as legacy speed class)
The Speed Class Rating guarantees a minimum rate at which data can be written to a card.
There are just four Speed Class Ratings: Class 2, Class 4, Class 6 and Class 10. The succeeding number indicates the number of megabytes per second (as a minimum) sustained write speed of a card.
UHS SPEED CLASS
UHS (Ultra High Speed) refers to the minimum sustained writing performance for recording video and came about in the advent of 4K capable video devices which needed faster write speeds.
There are two UHS ratings: UHS-I and UHS-III.
VIDEO SPEED CLASS
Video Speed Class provides equivalents to existing speed classes and adds new capture rates of 60 MB/s and 90 MB/s. This rating was created to enable higher video resolution and recording features such as multiple video streams, 360 degree capture, VR content, or 8K and higher resolution video.
To the uninitiated, the sheer number of symbols, numbers and letters that appear on an SD memory card can be overwhelming.
Below is how the three Speed Classes referred to above fit together, along with the rating/s you should be looking for, for your chosen application:
APPLICATION PERFORMANCE CLASS
The newest performance class from the SD Association, defines not only sequential read speeds but also mandates a minimum IOPS (Input/Output Operations Per Second) for reading and writing.
There are currently two Application Performance Classes:
Top line, when it comes to performance, SD memory cards are going from strength to strength.
The physical dimensions of these cards have not changed in almost 20 years, but the volume of data they can store has grown (from 2GB to 1TB), as has the speed at which they can read/write data. SD Express and microSD Express memory cards announced recently do not rely upon speed classes due to their rapid speeds.
Advancements in mobile and computing technology, mean we can expect the SD card evolution to continue (and at pace) as manufacturers strive to meet performance requirements of new data rich tech.
There are a vast array of different SD and microSD memory cards readily available online, which is great for consumers as we are typically told exactly which card we need for our new electronic device, and simply key it into our preferred search engine.
But for commercial users (manufacturers, designers, etc), it can be a minefield, and we definitely wouldn’t suggest you rely on your search engine or consumer branding to find the right data storage solution for your application.
If you want to secure the best flash memory solution for your application, contact the experts at Cardwave today. NOTE: We don’t simply supply flash memory! Our consultative approach means we work in partnership with our customers and the world’s leading flash memory manufacturers to deliver products and services that work for your business.
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