The NFC chip
At the heart of every NFC tag, sticker or product is an NFC ‘chip’ or ‘IC’ (integrated circuit). These tiny electronic devices store your information and control how it can be accessed.
NFC IC types
Different NFC chips have varying amounts of memory and features. The amount of memory will determine how much data you can store on your chip. Additional features can include password protection, scan counters or tamper detection.
The price that you pay for your tags and products will be very closely related to the quantities being made. High volume manufacture reduces the pricing significantly and therefore most tag production tends to lean towards a very small selection of chips. In reality, the NTAG213 and MIFARE Ultralight are the two most popular chips for use with mobile phones.
Genuine vs. fake
The vast majority of NFC chips available on NFC tags and products sold via retailers and large scale tag manufacturers are made by NXP Semiconductors. There are however, a number of non-genuine chips around particularly with the Ultralight. NFC.Today very strongly recommend using genuine chips and making sure you know your supplier and where they make the tags. The reliability and quality of non-genuine chips varies between not great and truly shocking. There aren’t going to be many projects which will find the savings worthwhile.
Choosing your NFC IC
Let’s keep it simple. For the vast majority of applications, use the NTAG213. Unless :
You need more memory. In which case your best option is usually the NTAG216. The 215 might be a little cheaper but it’s so rare that you probably won’t save much.
You need a product (wristband/keyfob). In which case, you might find more products available with the Ultralight chip. However, many Ultralight products have fake chips and the quality can be low. Purchase carefully.
You need tamper or authentication features. Then go for the NTAG213 TT or NTAG413 DNA.
NFC.Today take the view that the NFC tag should be an ID and link to data rather than the store of data itself. In which case, the standard NTAG213 should be more than enough even for longer tracking URLs.
However, if you really do need to store large data or aren’t sure if what you want to store will squeeze onto an Ultralight chip, then read our how much NFC tag memory you might need guide.
Popular NFC Chips
NXP’s NTAG series along with their Ultralight chip are by far the most common for mobile use. The basic details are listed here and there’s a breakdown of each of these features and chips below.
|Chip||Memory||User Memory||Max URL||Scan Counter||Password||SUN Auth|
Memory vs. user memory
Memory is the total amount of memory within the chip. Worth noting that relative to other memory devices such as USB sticks, etc, this is very, very small. In fact, most NFC tags can store no more than roughly a single sentence of text. However, within that memory space there are sections which are reserved for the function of the tag. For example, information regarding permission to change the data, the UID of the chip (which can’t be changed on genuine chips), and so on. This means that a user wishing to store data onto the tag can’t use all the available memory space and only the space minus this important data – the ‘user memory’.
To make it easier to understand what can actually be stored in this user memory space, the table shows the maximum length of a URL (web address) that can be stored on that tag.
Some NFC tags reserve a small amount of memory and have a feature which allows the tag to automatically store how many times it has been scanned. Note that if you are using the tag to count the number of visits to, say, a web page, then this isn’t a good way to do it. It is possible for a user to scan the tag, increase the count, but not visit the URL stored on the tag. For example, maybe the user didn’t have internet access or cancelled the pageview before the page got a chance to load.
Some NFC tags have a password feature which allows controlled access to view or change the data on the tag. From a mobile phone, an App is required for this. It’s a fairly low level of security but would stop a casual viewer changing data.
The new NTAG413 DNA tag contains a special feature allowing sections of data to be securely appended to the URL of the tag.
All the NTAG series and the MIFARE Ultralight® chips have a common set of features such as a seven byte (14 character) unique ID (UID), universal compatibility across all current mobile phones, tag locking ability and NFC Forum compatibility.
Other NFC chips
Obviously, the NTAG and MIFARE Ultralight® chips aren’t the only NFC chips on the market. And of course, NXP isn’t the only manufacturer with companies such as Infineon and STMicroelectronics also making NFC chips.
The reason NFC.Today tend to focus on the NTAG series is simply because they are the most widely available and universally compatible. Some of the other chips, such as the MIFARE Classic® for example, are not NFC Forum compatible. Most of the others would only be available as a specialist order in very high quantities.
MIFARE, MIFARE Ultralight, MIFARE Classic and MIFARE DESFire are registered trademarks of NXP B.V.