NXP Rolls MCU, NFC, and Security Together Into a One-chip Solution
At Embedded World 2023, NXP unveils a chip that integrates a microcontroller, an NFC front end, and security into a single IC.
We’re back again on day three of Embedded World 2023. We’ve seen a lot of interesting stuff here in Nuremberg this week. Today, we bring you coverage of the PN7642, a new near-field communication (NFC) + microcontroller (MCU) security IC announced this week by NXP Semiconductors.
NXP’s Fabrice Punch holding a board with the new NXP PN7642 today at Embedded World 2023.
In this article, we examine the key details of the PN7642, explain the significance of an MCU/NFC combined chip, and share insights from our interview with Fabrice Punch, marketing director at NXP Semiconductors.
Microcontroller and NFC All-on-one Chip
Combining an NFC front end, an MCU, and security onto one chip, NXP’s PN7642 serves as a high-performance NFC reader. It is designed to enable reliable contactless communication even in metal environments and battery-powered applications. The device offers high-output power at 2 W, along with high immunity against noise and low power card detection.
Combining an MCU and NFC on one chip, the PN7642 (left) serves as a high-performance NFC reader. This results in a much simpler design compared to a three-chip design (right).
“This is the first time that we will release to the market a microcontroller product which includes NFC connectivity—both a programmable MCU and embedded security,” says Punch. “The chip includes an NFC front end inside. It's one chip—not a combo, not a multi-chip module—it's really one piece of silicon.”
The PN7642 enables internal key storage and hardware crypto processing to accelerate the secure authentication in hardware—a process much faster than a pure software implementation, according to Punch. The device is GlobalPlatform security certified.
Because the PN7642 is highly integrated and customizable, it helps reduce the footprint and cost of NFC-based system designs, making the need for an additional MCU optional. The MCU side of the device embeds an Arm Cortex M33 core and 180 KB of programmable flash memory.
Offered in a VFBGA package, PN7642 provides a generous set of interfaces. For controller side interfaces, the device includes SPI, I2C, and an ISO7816 UART. On the host side of the chip, the device provides SPI, I2C, I3C, HSUART, and USB. Other on-chip resources include pulse-width modulation (PWM) and analog-to-digital converter (ADC) functionality.
Target Applications for the PN7642
According to Punch, target applications for the PN7642 divide into three areas: physical access control, authentication of consumables/accessories, and contactless data communication. Physical access designs include devices such as residential smart door locks/doorbells, corporate/hospitality locks, and electronic lockers.
Next, the authentication category comprises systems such as home appliances, printers, IoT device onboarding (gateways), and medical drug delivery devices. Finally, the contact data comms segment includes designs such as battery communication controllers (in light EVs), closed-loop payment systems, and trusted ID readers.
In our interview, Punch discussed all three types of use cases. But, for the purposes of this article, we’ll focus on the physical access control use case.
In the physical access control use case, Punch says that the PN7642 is used for the quick, flexible, and reliable daily locking/unlocking of smart locks using key fobs, wristbands, and smartphones. “For this use case, the PN7642 is really the solution that enables the most efficient bill of materials (BoM),” he says. “We offer a one chip solution with the right balance between the performance, system security, and level of the integration.”
In this secure physical access control use case, the PN7642 is used for the quick, flexible, and reliable daily locking/ unlocking of smart locks with key fobs or phones.
As shown in the diagram above, only the elements highlighted in blue are required when using the PN7642. “Of course, there may be additional IP blocks that can be added by engineers—like bluetooth or biometrics identification,” says Punch. “But the secure element here becomes optional because we already have in the PN7642 all the needed security features.”
“We already have the key storage and the crypto processing—and the secure element is not needed.”
Designers could add the secure element here as an option, for example, for supporting more algorithms, longer keys, or more keys. “But for this basic application—secure physical access control—we think that the secure element is no longer needed,” says Punch.
Meanwhile, on the back-end system, an additional MCU becomes optional. If, for some reason, the application does need another MCU, that MCU can be a relatively simple and cheap MCU because much of the processing needed is already available in the PN7642, according to Punch.
NXP Semiconductors is exhibiting this week at Embedded World. NXP’s booth is 4A-222.
All images used courtesy of NXP Semiconductors