In the previous video, we have discussed how Anker PowerIQ works.
But how do Qualcomm Quick charge and MediaTek Pump Express work?
What is spare current charging?
What is current modulation?
All of these questions will be answered in this video.
If there is anything unclear about the following video, or if you have any suggestions, do
not hesitate to leave a comment!
Qualcomm Quick Charge and MediaTek Pump Express are protocols through which a mobile phone
communicates to a charger in order to request a different voltage than five volts, either
to increase the charging efficiency at higher currents by matching the internal battery
voltage of the phone, also known from Huawei SuperCharge, or for the main reason:
The idea for the Quick Charge protocol originated before USB-C, which supports five ampère
of current, was common in mobile phones.
Due to the limited current the former USB-B connector could handle, they had to increase
another variable to increase the total charging wattage, which is the voltage.
A higher voltage at the same current does increase the power throughput without producing
any additional heat inside the copper wires of the USB cable.
This elevated voltage gets converted down to the Lithium-Ion or Lithium-Polymer battery
charging voltage of around four point three volts inside the phone using an integrated
buck converter.
The two early standards for requesting an elevated voltage from the power supply were
Qualcomm Quick Charging and MediaTek Pump Express.
While Qualcomm's protocol communicates to the charger utilizing the USB data lanes,
the original version of MediaTek PumpExpress utilized the main power lines themselves for
communication, by toggling the current drawing in specific intervals that represent information
interpreted by the power supply.
Also known as current modulation.
The first widespread version of Qualcomm quick charging was version two point zero.
It originally only supported the voltage steps of five volts, nine volts and twelve volts.
Pump Express version one supported a seven-volt level in between.
There was a so-called Revision B of Qualcomm Quick Charge two point zero, adding a twenty-volt
mode for future-proofness and support for laptops, also covering the usual fifteen-volt
requirement of larger tablets.
However, the charging protocols soon were revised into the next round in 2016.
Pump Express two point zero now had a voltage range of five to twenty volts with half-volt
steps, while Qualcomm Quick Charge had threee point six volts to twenty two at fifth volt
steps.
Pump Express version three works in a similar way as Huawei SuperCharge and OnePlus DashCharge,
where the mobile phone requests voltage adjustments from the charger, until the voltage that arrives
at the mobile phone matches the battery's internal voltage as accurately as possible.
This reduces heat production by removing the need for coarse voltage regulation of high
currents inside of the mobile phone.
More and more mobile phone manufacturers are implementing USB-C power delivery, which does
not use either of current modulation or data lanes for communication to the power supply,
but rather the dedicated power delivery communication lane of double-ending USB-C cables.
However, there is a serious limitation common in many mobile phones, deliberately induced
by manufacturers: While the mobile phone is being utilized, the charging speed gets drastically
reduced, rendering fast charging temporarily ineffective.
The correct way to do is, which is how laptops have been doing it since ever, is the spare
current method, where the charging speed is unaffected by device usage, because the device
utilizes the spare output power of the power supply to power the device components while
maintaining the original fast charging speed.