The Difference Between a TF Card and microSD Card
In general terms the TF card and microSD card are the same. They are the same in physical size and same in most technical terms. The two devices may be used in exchange with each other.
There are some technical differences between the two which will be explained later, for now, the biggest difference between a TF card and microSD card is the history of the name.
The TF card came out first. TF card or T-Flash or TransFlash was first to market from SanDisk in 2004. SanDisk, in partnership with Motorola, created the TF card specification. The TF card was the smallest read/write memory form factor and was designed for mobile devices (thus the small size).
TF cards are based on NAND1 memory. The TF card did not last long. At the end of 2004 the Secure Digital Association, which is the governing body over Secure Digital media, absorbed the TransFlash technology and re-branded as: microSD.
This implies, the life of the TF card ended in late 2004 and the microSD card has been available ever since. This will explain why you cannot find a “TF” branded card today (2020). The other reason you cannot find TF cards today is the maximium size of only 16MBs or 32MBs at the time of production. Today you cannot find any memory device with that small of gigabyte capacity.
Here is the technical difference between the two: Micro SD cards can support SDIO mode, which means they can perform tasks unrelated to memory, such as Bluetooth, GPS, and Near Field Communication. Whereas a TransFlash card cannot perform this kind of task.
SDIO mode stands for Secure Digital Input Output, a type of Secure Digital card interface. It may be used as an interface for input or output devices.
The SD Association devised a way to standardize the speed ratings for different cards. These are defined as ‘Speed Class’ and refer to the absolute minimum sustained write speeds. Cards can be rated as Class 2 (minimum write speed of 2MB/s), Class 4 (4MB/s), Class 6 (6MB/s) or Class 10 (10MB/s). It’s important to note that these are the minimum, so it’s entirely possible a card can achieve faster speeds.
NAND is not an acronym. Instead, the term is short for “NOT AND,” a Boolean operator and logic gate. The NAND operator produces a FALSE value only if both values of its two inputs are TRUE. It may be contrasted with the NOR operator, which only produces a TRUE value if both inputs are FALSE.