Mumbai: Back in November 2015, a Google engineer Benson Leung pointed out in a personal blog that Qualcomm’s quick charge (QC) technology and Type-C USB feature cannot co-exist as the later forbids the proprietary charging methods including used by QC2.0 and QC3.0.
According to Leung’s explanation, any device using Qualcomm’s QC cannot use Type-C spec, and two new flagship smartphones HTC 10 and LG G5 are doing exactly that.
He said that a USB Type-C cable works perfectly when the Vbus was fixed at 5V. "The Type-C spec specifically forbids proprietary charging methods that try to change Vbus beyond 5V," said Leung.
USB Type-C works fine with Qualcomm's QC2.0 and 3.0 use variable voltages on Vbus in order to get more power over the legacy USB A-to-microB cables.
However, as mentioned by Leung in his blog, a charger with a USB Type-C connector may employ additional charging methods to source power beyond what is allowed by the USB defined methods which totally works against the concept of QC.
Qualcomm’s response
While Leung has explained why USB Type-C and QC cannot co-exist due to incompatible charging standards, Qualcomm has given an official statement to Android Central, suggesting that QC is not dependent on the type of connector and no malfunctions regarding this issue has been reported.
Qualcomm Quick Charge is designed to be connector-independent. It can be implemented in a device that supports a variety of connectors, including USB Type-A, USB micro, USB Type-C, and others. When an OEM chooses to implement Quick Charge into their device, they can configure the voltage to fit within the specifications of the USB Type-C standard. We have received no reports of user experience or device malfunction issues with or without USB Type-C connectors. At Qualcomm Technologies, we are continuously working to provide the best solutions for our customers and consumers. Qualcomm Quick Charge is a leading edge fast charging solution with more than 70 devices and 200 accessories supporting one of the two most recent versions of Quick Charge, with even more currently in development.
While the statement leaves an air of mist surrounding the violations, it is safe to assume that the devices—LG G5 and HTC 10—are engineered to charge via QC via USB Type-C connector.
However, users should always be careful about using charging components that are directly supplied by the manufacturer. Duplicate chargers can trigger some phones to draw excessive current which can be dangerous.
