What is NFC?
NFC is an abbreviation of Near Field Connectivity. This is a simple radio technology that allows the transmission of data held nearby (< 10 cm). NFC technologies are based on the classic RFID of 13, 56 MHz High Frequency (HF)
The NFC standard now enables various transmission speeds of data up to 424 Kbit/s. The main NFC communication method between devices connected is the same as the classic RFID of 13, 56 MHz, which has both a leader and a subject. The master is the issuer or reader, while the subject is a tag or a card.
How is NFC working?
The initiator (emitter) actively produces an RF field via magnetic fields between parallel circuit NFC antennas that may provide a passive goal (Tag).
Emitter antennas and the tag are connected via electrostatic energy, and best this system can be seen as an air-core converter, where the reader acts as a primary winding and the tag as a secondary winding: the alternative charging current through the superior (Emitter) induces an airfield that induces currents into the secondary belt (Tag). The tag may utilize the field current to power itself. In this instance, no battery is needed in reading or write mode to access it. The NFC tag chip gets all power required to function from the viewer’s produced magnetic field via its receiver coil.
What is the usage of NFC Technology?
NFC is an emerging technology that needs to link electrical devices wirelessly. To communicate with hardware devices suitable with NFC and enable new services, such as contactless payment, NFC has been increasingly implemented into devices.
Because NFC tags do not require a power source to be included since they may be driven by the energy the reader emits, it may take extremely basic operating systems such as electric powered tags, NFC stickers, NFC card manufacturers, and even rings.
The compatibility of the chip
First of all: which reader has been used to read or write the attributes. If we cannot read or code a tag, it isn’t very worthy. It is a smart option to confirm that the NFC Chip maker and the NFC Viewer are mutually compatible. See also the NFC Devices Guide.
There are a few factors.
You may pick NTAG® or ICODE® chips if you wish to utilize a smartphone.
Ø ISO14443 vs ISO15693
Whether you use a different reader, it is important to verify if it is the correct one. The chips of type NTAG® and MIFARE® are ISO 14443 and ICODE® of type ISO 15693.
Ø Pre-existing systems
You may verify the kind of chip being used using a smartphone or NFC reader when you are not sure of the technicalities of your NFC Reader but are currently utilizing Microprocessor controlled. You should also ensure that the organization you are using is “open” and enables multiple providers to use Tags.
The inductance of the Antenna:
An NFC tag must have a PCB NFC antenna to connect and be powered. The antenna design process begins with the NFC chip approximate solution and its loop antenna:
- VOC is the open-circuit voltage of the loop antenna caused by a magnetic field
- Ra is the corresponding loop antenna resistance
- La is the comparable loop antenna inductance
- Rs is the NFC chip’s serial equivalent resistance
- Cs is the conventional equivalent NFC chip tuning capability
An inductance La with a very modest loss resistors Ra may define the antenna. When the transmitter in the loop antenna induces a magnetic field, there is a current there, and an open-circuit voltage Voc emerges at its terminals. The resistive input Rs and a built-in tuning condenser Cs may define the NFC PCB chip.
For the final approximate solution of the network containing the NFC integrated circuit and its integrated circuit, the resistors Ra and R are added together.
The NFC IC resistor Rs and the resistive antenna Ra and the built-in condenser Cs create a resonant RLC circuit with antenna inductor La.
The formula shows the frequency response of an RLC series:
- F is the frequency of resonance (Hz)
- L is the circuit inductance equivalent (H)
- C is the equivalent circuit capacitance (F)
The only parameter unknown to the formula is the inductance value L. It is so isolated that it is computed:
The shape of the antenna:
It is feasible to design a loop antenna on a PCB with a certain inductance and geometrically restricted. An antenna may be rectangular, square, circular, octagonal, or even hexagonal. Every form correlates to a particular form which shows the comparable inductivity according to size, the number of rounds, track width, copper thickness, and many other characteristics.
The emergence of internet antenna geometry simulators is an alternative to the laborious computations in the preceding stage. These calculators are manufactured by people or experts and aimed towards
Reduce frequency response. As it is impossible to ascertain the computations made by these internet tools, calculators showing references and formulae used or produced by specialist firms are strongly recommended.
Another key component is the NFC manufacturers have rewritable user memory. The storage should be selected depending on the quantity of data to be used. Labels with less capacity are often less costly.
Here are a few such instances.
- An NTAG210 or NTAG213 chip is sufficient to program a tag with a URL or basic text such as code (containing about 40 and 140 characters, respectively).
- For a computational software business card (V-Card), it is recommended to use a Tag with larger memory, for example, NTAG216.
Tags with a complex framework are also available for specific uses, such as the EV2 chip.
The NFC chip manufacturers give information that is always “visible” without security, viewable to everyone who reads the tag with a smartphone or NFC reader. Just need to use a processor that enables encryption to prevent this.
Open Source Antennas:
Certain manufacturers offer entire solutions for electrical developers, such as designs, application instructions, and even EDA files, to assist the installation of their NFC ICs.
This is the case with NXP, which sells integrated circuits for their NFC range NTAG is a comprehensive handbook with NFC antenna design guidelines and excellent computation software for rectangular and circular antennas, Gerber and Eagle files for various antenna classes.
NXP gives the Eagle data of an antenna produced by its engineers and already implemented in some of its devices for this class. The key benefit of this design is the simulation, correction, and optimization.
The electrical schema is created on EAGLE PCB.
The built-in NFC NT3H1101, the only active ingredient of the circuit, is coupled to the passive parts utilizing the datasheet specification of its connections.
The selection of the correct NFC PCB manufacturer is a significant concern. The term quality may signify a range of various things and is not specified and may be vague in itself.
However, in essence, the NFC PCB quality implies that the panel comes in and draws – no mistakes.
- The quality of PCBs might indicate a multitude of aspects:
- Board in the proper size
- All hole drilled and placed precisely
- Test bare board passes
- Minimum bending of the board (although some of this can be due to board design)
- A lot of additional problems.
The performance should always remain excellent and not decline once the primary orders have been acquired successfully.
As errors might damage the business of the PCB assembly or the equipment maker, confirming the quality of the selected supplier is essential. Other non-competitive firms may be able to enquire about the continuous quality.
Capacity to satisfy requirements:
The first issue is if the maker of NFC PCBs can meet the requirements. In principle, the files may be accepted in the forms they are supplied (typically not an issue, since formats are usually common) and also generate boards with the appropriate specification: number of lines, kind of PCB materials, tolerances, particular requirements, etc.
A comprehensive checklist is worthwhile to ensure they are all able to fulfill them.
Cost of manufacture of PCBs:
The cist is an important element. Cost reduction is part of an effective product. However, attention must be paid to ensuring that the cost is not excessively low.
The lowest cost contributes much to any choice, but it has been claimed that the delight of cheap costs is gone long before the complaint of bad quality has been addressed.
To reduce the total price but for the desired product, the balance between price and performance is essential.
Watch out from Brokers:
It may be surprising that most of the so-called NFC PCB manufacturers are brokers who receive orders and send them to a manufacturing business. Be careful since the standards and regulations that may have to be set on the board cannot be guaranteed.
Although some competent brokers may be able to place orders that are helpful in general, the best thing to do is guarantee that the genuine NFC PCB manufacturer communicates.