There are a few things I noticed and examined for two different fast charging standards:

  • MediaTek PumpExpress works without any data communications with the charger. Output 2 from my USB multimeter has no data connections, so I connected the cable to output 2 to disable data communications. The multimeter shows some varying power currents, so it is possible that the communication happens via power impulses. But it needs to go up by steps of 5V,7V,9V,12V.
  • Qualcomm FastCharge jumps to desired voltage (9V) two seconds after inserting, because it uses the USB dats ports as handshake gateway, which does accordingly not work, when being used with port 2 with handicapped data ports onthe USB multimeter. How can I do manual voltage requests? QuickCharge 3.0, unlike 2.0, has no fixed levels, but can freely deliver any voltage range supported by the charger.
  • For Qualcomm's wireless fast charging, the wireless charging plate itself communicaties to the USB charger through the cable. Probably, there is also some communication to the phone, but I am not quite sure.

What are the technical details behind the charging standards and how they work under the hood? Are they only software-based?

Are there documentated? Can I safely just supply 7V or 9V using a laboratory power supply, without using any of these standards?
If they are only software-based, does that mean that I can use Qualcomm's Quick Charging standard over MediaTek processors and ViceVersa?

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    \$\begingroup\$ Could you separate the wired charging and wireless charging into 2 separate questions? Otherwise, your question is too broad. \$\endgroup\$ – Nick Alexeev Feb 14 '18 at 0:20

That Pump express uses USB 3.0 Power Delivery standard according to their website. PD is well documented through the USB IF.

Qualcomm does not publicly distribute their Quick charge standards.

Qi is an open standard through the Wireless power consortium, but you need to register to download it.

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  • \$\begingroup\$ So does it mean, that PumpExpress is just a rebranded name without any other changes? \$\endgroup\$ – neverMind9 Feb 14 '18 at 8:44
  • \$\begingroup\$ Qualcomm does not publicly distribute it? Oh no, yet another paranoid patent monster, who does not help and contribute to world. Then, how do budget charger manufacturers such as Powstro (archive.li/IOwlr) get access to it?. \$\endgroup\$ – neverMind9 Feb 14 '18 at 8:46
  • \$\begingroup\$ Here is an article: androidpit.com/charging-standards-comparison | I am glad, that the open-source-hardware standard is going to be enforced by Google, who is considered effectively the Internet's invincible superpower. Qualcomm's quick charging is not bad and has the widest market share so far, but we do not need yet another closed-source proprietary monster. Alternatively, they could openly release their standard. \$\endgroup\$ – neverMind9 Feb 14 '18 at 8:55
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    \$\begingroup\$ Qualcomm is notorious for locking everything down with a non-disclosure agreement. \$\endgroup\$ – jms Feb 14 '18 at 8:59
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    \$\begingroup\$ @TechLord, the AndroidPit article is quite a garbage. They have no clue how PD complexity is compared to QC. Current list (Feb 2018) of devices supporting QC (2.0 and 3.0) has more than 870 entries. And I can't find out how many smartphones have PD. In 2016 the QC/PD ratio was about 100:4. qualcomm.com/documents/quick-charge-device-list \$\endgroup\$ – Ale..chenski Feb 19 '18 at 0:01

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