Quick Charge 2.0 addresses the rising power requirements of features-packed mobile devices.

Power-hungry apps are spurring semiconductor companies to develop solutions, which will support faster charging of mobile devices. One such release getting traction is Quick Charge 2.0, a proprietary protocol from Qualcomm Technologies Inc. Targeting smartphones and tablet PCs, it accelerates the process by up to 75 percent compared with the conventional USB counterpart.

On the charger side, chipmakers lead the rollout of components. Dialog Semiconductor PLC has launched the iW620 AC/DC adapter interface chip for smartphone and tablet computer chargers. The device resides on the secondary side of the power supply and works with the company’s iW1760 primary-side digital pulse width modulation controller.

In terminal products, there is Qualcomm embedding Quick Charge 2.0 in its line of Snapdragon smartphone processors. It also offers a stand-alone IC design to mobile device manufacturers.

“As a leading supplier of high-power density, fast-charge AC/DC controller solutions for mobile device chargers, we began seeing smartphone and tablet PC rapid charging gaining traction very early this year. Qualcomm’s Quick Charge 2.0 is one of several protocols enabling this trend,” said Scott Brown, marketing divisional director of Dialog Semiconductor's power conversion business group. “We are one of the first to ship compatible AC/DC adapter ICs, starting with deliveries to major telecom service providers in Japan’s smartphone power supply market.”

“Quick Charge 2.0 works with standard USB cables and is compatible with USB BC 1.2 dedicated charging ports,” said Brown.

The USB standard specifies 5V supply. USB connectors can handle up to 2A, limiting maximum power from the corresponding charger to 10W or less.

Products based on Quick Charge 2.0 run at 5, 9 and 12V for class A, and up to 20V for class B, delivering 10 to 40W via USB. This is because the technology permits terminal devices and AC/DC wall chargers to communicate. The former, for instance, can ask for a higher voltage to speed up power transfer for faster charging.

Early traction in Japan

The market is beginning to embrace Qualcomm’s Quick Charge 2.0. Dialog Semiconductor has started shipping compatible iW620 AC/DC adapter interface ICs to customers, including Hosiden Corp. The last is a major Japan manufacturer of chargers for mobile devices. Key mobile operator NTT DoCoMo, meanwhile, is now one of the first carriers there to offer enabled phone chargers.

One challenge lies in providing higher power without increasing charger size. Brown said Dialog Semiconductor’s Quick Charge 2.0 solutions have greater efficiency of as much as 88 percent without additional components. “This allows higher power density for smaller form-factor rapid charging adapters.”

As QC, Qualcomm is implementing a certification program, with UL as the testing and certification laboratory for Quick Charge 2.0 products. The former will authorize approved suppliers of smartphones, tablet PCs, chargers and adapter chipsets to use the Qualcomm Quick Charge 2.0 logo to ensure compatibility and interoperability.

Brown said other applications needing higher than 10W can benefit from better power transfer and faster charging. These products include larger devices such as slim notebook PCs and digital cameras.