13.56 MHzNFC & RFID
A tap that does the job.
NFC is radio over centimetres: the phone or the card has to touch the device. That is exactly why it suits access control, authenticity checks and one-tap configuration - with no pairing.
In short
What NFC is, and where RFID fits
NFC (Near Field Communication) runs at 13.56 MHz and exchanges data over a few centimetres - usually up to 4 cm. The reader creates a magnetic field that powers the passive tag, so tags need no battery and can be a sticker, a key fob or a card.
RFID is the wider family NFC belongs to. Low-frequency 125 kHz is used in older access cards, and UHF RFID (860-960 MHz) in logistics, where tags are read from metres away. NFC adds the NFC Forum standards and a reader built into every modern smartphone.
For a device that means three scenarios: the phone reads a tag (a product, a sign, a document), the phone writes to the device (configuration without buttons or a display), or the device reads a card (access, tracking). The rate - 106 to 424 kbit/s - is enough for an identifier, a key or a few kilobytes of settings.
When
When NFC is the right choice
Choose NFC when
- A person has to tap to confirm
- Tags must be cheap and battery-free
- You configure a device with no display or buttons
- The phone should read without an installed app
It's not for you if
- You need range beyond a few centimetres
- You need a continuous stream of data
- The device has to exchange data with nobody nearby
| Technology | Range | Tag battery | Phone |
|---|---|---|---|
| NFC, 13.56 MHz | up to ~4 cm | Not needed | Yes, in most |
| RFID, 125 kHz | up to ~10 cm | Not needed | No |
| UHF RFID | up to a few metres | Not needed | No |
| Bluetooth LE | 10-100 m | Needed | Yes |
What we build
Devices with NFC
Examples of devices we design - not a client list.
01
Access control
A reader for cards and phones on a door, a cabinet or a machine, with a local list of permissions and an event log.
02
Authenticity tags
Tags with a cryptographic signature that a phone checks with a tap - for products, documents and spare parts.
03
Tap to configure
A device with no display that receives its settings from a phone: network, address, operating mode.
04
Tool tracking
A tag on every tool or asset and a reader at the store-room door or the workbench.
Parts
Chips and tags
The choice depends on range, antenna shape and availability. The BOM always carries an alternate.
- NXP PN7150
- NFC controller for readers
- ST ST25R
- Readers with longer range
- NTAG 21x / NTAG 424
- Tags, incl. cryptographically signed
- ESP32 / STM32
- The control around the reader
Questions about NFC
Can a phone read the tag without an app?
Yes, for standard records (NDEF) such as a link or text - iPhone and Android open them directly. More involved operations, such as writing to the device, need an app, which our software partner CulSoft builds.
What is the range of NFC?
Usually up to 4 cm. That is a feature: the exchange happens only when someone deliberately brings the phone or card close.
Is NFC secure enough for access control?
It depends on the tag. Plain tags can be copied; for access and authenticity we use tags with cryptographic protection, verified by the device.
Does NFC work through metal?
Metal detunes the antenna. In a metal enclosure we design the antenna and its placement so reading stays reliable, or use on-metal tags.