1 background
NFC is short-range wireless communication. It is a wireless technology initiated by NXP, which is jointly promoted by famous manufacturers such as Nokia and Sony. It combines inductive card reader, inductive card and point-to-point function on a single chip, which can be used within a short distance. Compatible devices for identification and data exchange. NFC has the characteristics of two-way connection and identification, working in the frequency range of 13.56MHz, and the working distance is close to 10 cm. NFC technology promotes standardization under the ISO 18092, ECMA 340 and ETSI TS 102 190 frameworks, and is also compatible with the widely used ISO 14443 Type-A, B and Felica standard contactless smart cards.
Compliant with the latest NFC specifications developed by the European Telecommunications Standards Institute (ETSI), the PN544 provides mobile phone manufacturers and telecom operators with a fully compatible platform for the next generation of NFC devices and services: the PN544 is fully compatible with all available single-line Protocol (SWP) The NFC specification for connecting the SIM card to the Host Controller Interface (HCI).
The PN65O is the PN544 plus NXP's SmartMX security module, and the PN544 and PN65O hardware PINs are fully compatible with the PIN. At the same time, the PN65O / PN544 offers a variety of host interface options to ensure that handset manufacturers can easily integrate High Speed ​​UART, SPI, I2C, and support multiple RF interface protocols: ISO14443A/B, ISO15693, MIFARE, Felica. In addition, NXP Work closely with leading SIM card manufacturers such as Gemalto, Oberthur Technologies and Giesecke & Devrient to ensure interoperability of SWP interfaces including MIFARE technology.
2 NFC e-wallet overall structure
2.1 Block diagram of NFC PN544 / PN65O
Figure 1 below shows the block diagram of the NFC PN544 / PN65O.
Figure 1 NFC PN544 / PN65O hardware circuit block diagram
2.2 Advantages of PN544 and PN65O
(1) Small size for easy size optimization
(2) Low power consumption
(3) Battery shutdown and low battery operation mode
(4) Optional platform-independent software stack
(5) Provide GPIO PORT for external unit control
(6) Interrupt IRQ to make command communication of external control unit easier
(7) Support security unit control interface
(8) Integrated power control unit
3 About NXP's latest NFC e-wallet solution
The NFC e-wallet function is based on the mobile phone as a trading platform. The PN544 NFC controller (the PN65O has a built-in security module) and the security module implement mobile payment and data exchange functions.
3.1 RF section
The NFC RF circuit is composed of EMC filter circuit, matching circuit, receiving circuit and antenna.
3.2 EMC circuit
Since the system is based on an operating frequency of 13.56 MHz. This frequency is generated by a quartz crystal. At the same time, high-order harmonics are generated. In order to comply with the internal electromagnetic compatibility rules, higher-order harmonics of three, five, and five times of 13.56 MHz must be appropriately suppressed. Therefore, the EMC circuit is configured as an LC low-pass filter for filtering out higher harmonics.
3.3 Antenna matching circuit
Since the antenna coil itself is a low-impedance device, in order to maximize the transfer of energy from the NFC IC to the antenna, a matching circuit must be added between the antenna and the NFC IC. Eliminate the energy loss caused by signal reflection caused by mismatch.
Icicle & Curtain Lights
The curtain light is mainly composed of a light string and a fixing hook; the light string is formed by connecting light bulb and wire; the fixing hook is a fitting having a wire groove and a hook, and the hook is formed above the wire groove. According to a certain shape, the wires on the light string can be fixed in the wire trough, so that various styles of curtain lights can be assembled., and the whole curtain light can be hung on the frame of the window and door through the hook when in use, and with the light bulb on the light chain to achieve the effect of dressing up windows and doors.
Usage one of Curtain lights: decorative bedroom
In fact, curtain lights are generally made up of a combination of small light strings of different colors, so you can transform a lot of shapes, decorate in all aspects, you can choose a part of the curtain light string, hanging on both sides of bedroom curtains and bedroom door, the ceiling can also be combined with some romantic patterns, and if the light selection is softer, it must very beautiful when the advent of the night lights come on.
Usage two of Curtain lights: decorative bed
The curtain and the bed curtain have similar effect , it can be operated if your bed with a bedpost or a bed curtain, if all the light string of the curtain light are hung on the bed or mattress, or directly take the light as a curtain and it looks like a waterfall when turn it on at night .
Usage three of Curtain lights: decorative wall surface
Curtain lights can be used to decorate walls, it is not only simply hanging on the wall as decoration, but also can be decorated with some murals or room structure, even it can be combined into a pattern or letter and so on. It is convenient to operate and very innovative.
Usage four of Curtain lights: decorative windows
The curtain lights is playing a major role to decorate windows, but the new method certainly not an ordinary decoration, it not only can be decorated on the window frame, but also can use as curtain, and it can sew special pattern on the curtains, then a beautiful pattern will be appeared when you draw the curtain at night.
Usage five of Curtain lights: decorative items
There are several kinds of items in the family unused and not pretty, and the key is that they are indispensable items. Such items are often incongruous in space and obtrusive, so you can use the curtain lights to decorate them, to wrap around them to create different scenery, like some toys can also be decorated.
Usage six of Curtain lights: decorative balcony
The monotonous balcony can also be very romantic. Choose star-shaped curtain light to decorate on the side of the balcony or on the balcony of the plant. Such a balcony is very special.
Icicle & Curtain Lights,LED Rubber Icicle Light,LED Mesh Lights,LED Net Curtain Light
Heshan Jianhao Lighting Industrial Co., Ltd. , https://www.sunclubtw.com