What is QC 3.0?

The battery capacity of smart phones is getting larger and larger. In addition to power saving, charging speed has become a feature that users are paying more and more attention to. Qualcomm’s Quick Charge technology has become one of the models in the industry. Following the Quick Charge 2.0 specification, the latest Quick Charge 3.0 technology (referred to as QC3.0), the general mobile phone only needs to be charged for about 35 minutes, and the power is It can be increased from 0% to 80%; while traditional mobile devices that do not use Quick Charge technology, it may take about 1.5 hours.

QC3.0 is backward compatible with the previous Quick Charge version, and can support the latest USB type-c connector; it is more flexible in charging options, QC2.0 provides four voltage options of 5V / 9V / 12V / 20V , And QC3.0 provides flexible selection of different voltages in the voltage range of 3.6V to 20V in increments of every 200mV. This allows the mobile phone to select the most suitable voltage to achieve the ideal charging current, thereby minimizing power loss, improving charging efficiency and improving thermal performance.

Compared with QC 2.0, QC 3.0 has the same charging speed and almost the same power output. The 8% benefit comes from the improvement of charging efficiency. It depends on how the power is delivered to the device. QC 2.0 is a stepped voltage, divided into 5V, 9V, 12V and 20V, which means that the charging voltage is fixed. The QC 3.0 charging voltage is “smooth”, suitable for voltages between 3.7-20V, and can accurately change the voltage, increasing the charging efficiency.

The voltage range of QC fast charge charging, in the above chart (assuming that the charging current is the same), you can see the difference in voltage output of the three charging technologies.
The standard QC voltage is 5V (blue line), the voltage of QC 2.0 is gradually increasing (orange line), and QC 3.0 can be variable in the entire voltage range (yellow line).
The advantage of QC 3.0 is that it can provide the best voltage under the precise requirements of the battery, so it is always charged at the fastest speed.
QC 2.0 is a staged voltage, and its efficiency is lower than QC 3.0, but it can still provide charging speed.
While the standard QC charging is maintained at 5V, the charging speed is slower.
This is the advantage of QC 3.0, or to put it simply, QC 3.0 is smarter and can provide faster charging speeds at the same power.

Now, Qualcomm’s fast charging technology maintains backward compatibility. Meaning: When charging on a smartphone, it will safely receive the maximum power of any certified charging device. But if you try to charge a newer mobile phone with an old low-power charger, the optimal charging speed cannot be achieved.