Integrated wireless phone charging might not be one of the first things consumers consider when it’s time to buy a
new
car, but it’s becoming an expectation as a key component of a model’s infotainment system.
The convenience and added
safety of having an easily accessible charger always available has resulted in wireless charging becoming
ubiquitous
for
car manufacturers as another way to enhance user experience. And not just for high-end trim packages or luxury
brands;
every major automotive manufacturer offers this feature across more than a hundred models.
The vast majority of these charging units are based on the Qi wireless charging standard, which is managed by the
Wireless Power Consortium (WPC) , the global
standard
development body for wireless power. Qi is used in most major
smartphones, including Apple and Samsung models, and has become the industry standard for in-vehicle charging. There
are
a few reasons for this, including its recognition in the industry, the WPC’s commitment to innovation and evolving
the
standard, and a broad range of third-party Qi accessories. The WPC also has a highly regarded certification process
that
ensures charging experiences meet consumer expectations.
NXP and the Qi-Standard
NXP has a proven track record of providing high-performance MWCT MCUs for Qi products, including being the global
leader
in integrated in-vehicle wireless power. As a result, we’ve established ourselves as thought leaders in wireless
power
and have been working with the WPC since the beginning of the standard. This includes participation in various WPC
working groups and support to drive the specification through its evolution. We also understand the design
challenges
that come with developing in-vehicle applications, particularly complex electromagnetic compatibility (EMC) design
and
integration that comes with managing reliable performance.
Device makers require custom wireless charging designs, which result in schematic reviews and software changes
specific
to each customer, depending on the specifications of the end design. Our expansive MCU portfolio covers the broad
power
range of devices that feature wireless charging, from 1W to 15W driven by Qi spec and up to 50W driven by
proprietary
protocols. Beyond the devices, we also provide certified software and hardware designs and support.
Two NXP product families, in particular, are helping to shape Qi performance and adoption, the MWCT2xxxS and
MWCT2xD2A
wireless charging ICs. On 26 November 2024, NXP's Magnetic Power Profile (MPP) multi-device wireless charging
transmitter using the MWCT2xD2A MCU passed the Qi2.0 MPP compliance testing and IOP testing. This is a key
milestone
in
Qi compliance, as Qi2.0 is the latest WPC standard and the MPP ensures that the wireless charging transmitter and
receiver coils are aligned perfectly for efficient power transfer.
NXP’s Qi2.0-certified MPP multidevice wireless charging transmitter
On-Chip Authentication: A New Era for In-Vehicle Charging
OEMs and developers face some very specific challenges when integrating wireless charging, including EMC, power
output,
and authentication. Today, standard wireless charging requires a dedicated MCU to control the charger and a secure
element to ensure the charger is actually Qi-compliant. This is driven by an update in Qi 1.3 that requires
hardware-based authentication which protects users from damage that can be done to their devices by using
counterfeit
products. This is a great feature for users, but for designers, a higher number of distinct parts adds complexity to
the
design. It also increases the cost of materials (BOM) to have two distinct parts, one of the key pressures facing
original design manufacturers (ODMs).
With the introduction of the MWCT2xxxS and MWCT2xD2A families, we’ve built authentication into the chip, eliminating
the
need for a separate secure element and streamlining the BOM. This approach leverages the NXP EdgeLock 2GO service to
connect to the WPC and generate the authentication certificate. The customer or authorized 3rd party can then
download
their unique certificate onto each MCU for production. Developers will be able to spend less time on external secure
element integration into the system, which is time-consuming. The MWCT2xxxS and MWCT2xxxA families also feature two
devices for dual charging driven by one MWCT MCU, so instead of needing two chips for this functionality, ODMs can
offer
this feature with a single chip.
NXP’s wireless power portfolio supports devices designed for in-vehicle, consumer
and industrial wireless charging
solutions
Ready for the Future of Wireless Charging
The MWCT2xxxS and MWCT2xD2A families
also consist of MCUs tailored to the consumer market segment which can be used
for
wireless charging stands and wireless charging cases. This extends the wireless charging technology with a full
spectrum
of charging options to support diverse markets including automotive, healthcare and IoT, among several
others.
Like any technology standard, Qi will continue to evolve and require new specification releases. This would typically
require design changes from device makers to achieve certification or maintain compliance. These MWCT2xxxS and
MWCT2xD2A
devices provide future-proofing for wireless charging designs with flexible SW and OTA FW updates, so as new Qi
standards are introduced, existing chips can stay in service with just a software update. These new families also
cover
a wide range of memory requirements with options ranging from 128 kB to 4 MB for a wide scope of application on top
of
Qi charging, for example, CAN and LIN communication with cars, enabled by TJAxxxx transceivers and
NFC for card
protection, low power wake-up of the charging controller and digital key functionality, enabled by NCx3321.
The introduction of on-chip authentication will make a dramatic difference for OEMs that will no longer be required
to
add a separate secure element for Qi authentication, reducing the overall cost of the wireless charging module. NXP
has
more than 30 engineers, with deep expertise and experience across regions, dedicated to delivering innovative MWCT
system solutions as the future of wireless charging evolves. Visit our Wireless Power page to further explore our
wireless charging portfolio.
