Quick Charge

Quick Charge (QC) is a proprietary battery charging protocol developed by Qualcomm, used for managing power delivered over USB, mainly by communicating to the power supply and negotiating a voltage. Quick Charge is used by devices such as mobile phones which run on Qualcomm system-on-chip (SoCs), and by some chargers; Both device and charger must implement QC for QC charging to happen; if one doesn't implement it, regular USB charging happens. QC charges batteries in devices faster than standard USB allows by increasing the output voltage supplied by the USB charger, while adopting techniques to prevent the battery damage caused by uncontrolled fast charging and regulating the incoming voltage internally. Many chargers that implement Quick Charge 2.0 and later are wall adaptors, but it is implemented on some in-car chargers, and some power banks use it to both receive and deliver charge. Quick Charge is also used by other manufacturers' proprietary rapid-charging systems.