The internet of things will make wireless charging a more urgent issue than it has been for smartphones, but the technology has suffered from a surfeit of would-be standards. Now two of the three candidate groups, the Alliance for Wireless Power (A4WP) and the Power Matters Alliance (PMA) are to merge, raising hopes of a single platform emerging to charge devices without cables.
The two bodies had already made overtures to one another almost a year ago when they announced a common certification program, but full merger should result in a combined technology with improved economies of scale. This is vital for any group targeting mass market consumer electronics (as opposed to the higher echelons of wireless charging, such as electric car systems). However, the two bodies will still lag behind the third would-be standard, Qi from the Wireless Power Consortium (WPC), which gained early support from the handset business and is embedded in well over 300 products.
The merger of the A4WP and PMA not only brings them closer to that kind of scale, but combines two different approaches to wireless charging – hopefully to achieve the best of both worlds, rather than market confusion. Initially at least, they will mainly focus on combined marketing and ecosystem building, while keeping both technologies available, but over time, mutual certification should evolve into a unified offering.
The A4WP has tended to present itself as the technically more advanced, with its Rezence platform based on near-field magnetic resonance running in 6.78MHz spectrum. The PMA’s Power 2.0, like Qi, is based on an older magnetic induction approach but has achieved better commercial presence than its new partner to date. For instance, it is supported by AT&T and scored a notable victory when Starbucks agreed to install the technology in its US coffee shops.
There are pros and cons to the two main technologies. Magnetic resonance allows for a larger charging field than magnetic induction, but charging multiple devices at the same time can increase charging time by sharing current, some experts argue, and the technology is only just becoming commercial. Meanwhile, magnetic induction ensures peak electrical transfer, but devices cannot be moved around very much while charging.
Ron Resnick, president of PMA, said the merger “assures decision makers throughout the industry of responsible stewardship of these essential contributing technologies.” The groups said they expect the merger to be complete by the middle of this year but they have not yet agreed on a name for the merged organization. Both initiatives were founded in 2012 and feature heavyweight backers, though many (like Qualcomm) have also joined the WPC. The A4WP includes Broadcom, Intel, Qualcomm and Samsung among its members, while the PMA has AT&T, Duracell, Powermat and Starbucks.
Wireless device charging will really gain momentum if the WPC will also combine its efforts with those of its rivals (though individual vendors are already looking to bridge the divide, as Freescale does with its recently announced multi-standard charging chip, which can support Power 2.0 or Qi). John Perzow, a VP of development at the WPC, told the Wall Street Journal that his group would be “willing and able” to have discussions with the others about combining its efforts with theirs.
Aside from these main groups, there are many other developments in the wireless charging field, some focused on other sectors, such as cars, some on further pushing the technology boundaries. There are several start-ups in both cases, such as Ossia and Energous, and of course, always the lurking possibility that Apple, which has not supported the technology in the iDevices yet, will use its own system rather than any of those on the open market.
And just to demonstrate the gap between the rival A4WP+PMA in its fight against the WPC’s Qi standard, both Toshiba and Active-Semi used CES as the staging ground to launch new Qi products – which use resonant inductive coupling to wirelessly transfer power, as opposed to the
Toshiba has launched a pair of devices; the TC7765WBG wireless power receiver integrated circuit (the bit that goes in the device), and the TB6865AFG Enhanced Version transmitter (the one that goes in the charger). Both adhere to the WPC’s Qi 1.1 specification, and sample shipments begin at the end of this month, with mass production scheduled for June.
Toshiba cites growing demand for higher-powered wireless charging as the reason behind increasing the receiver’s voltage from 5V to 7-12V. The transmitter’s design has been revised, based on a new peripheral circuit configuration, and its software has been updated.
The transmitter can comfortably power 10-watt class devices, such as phones and tablets, but the industry has some way to go before wireless power can be used to power larger devices in the 100-watt range. Nonetheless, Toshiba says the design allows maker to easily incorporate its new chips into their designs, reducing development times.
Active-Semi, meanwhile, announced the availability of a 15W transmitter, also Qi-certified, which claims “the industry’s highest efficiency with the smallest system footprint and BOM thanks to the single-IC based architecture.” The new power application controller module, called the PAC5220, is aimed at charging phones and tablets, but Active Semi says it is able to scale up to 65-watts – enough to power laptops.
“Our customers value the capability to scale wireless charging to higher power levels as it secures their investments for future emerging opportunities,” said Mark Cieri, Active-Semi’s VP Sales and Marketing. “With the addition of the new medium power solutions (5-120W), our 15W solution offers a complete platform that is scalable, configurable and now spans smartphones to laptops.”