Click to view our Accessibility Statement or contact us with accessibility-related questions
zanzabar
22
Aug 29, 2017
It is unsafe to use a type a to type c cable in a QC port. this is a terrible idea.
azfever
0
Aug 30, 2017
zanzabarWhy is it unsafe?
zanzabar
22
Aug 30, 2017
azfeverQC puts voltage over the data pins. If for some reason you hook a type c item to it or a hub, then have a fake type C device that supports QC 3 or lower it will kill everything. That is not likely to happen, but it could.
You can also only change at 1A with an a to c cable.
SourBerrySteaks
3
Aug 30, 2017
zanzabarMy phone, from the manufacturer, came with a qc 3.0 charger that has a usb-a on the base and usb-a to usb-c cable was supplied as the phone's port is usb-c.
Manufacturer Charger block input is: 100-200v 50/60hz 5a Output is: 5v 3A, 9v 2A, 12V 1.5A
Absolutely no issues and I've had it for over a year.
zanzabar
22
Aug 30, 2017
SourBerrySteaksdo you have last years lg or htc. those are not on spec.
makats
51
Sep 20, 2017
zanzabarMy Google Pixel XL came with C-to-C cable, A-to-C cable, AND a A-to-C dongle in the box...
Can't imagine that google would ship their phone with something that can potentially brake it (and other components).
zanzabar
22
Sep 20, 2017
makatsthe A to C is for data transfers, you should also never plug it into a QC brick. if you charge with an a to c it is fine, but it will only pull around 1 amp.
makats
51
Sep 20, 2017
zanzabarso are you saying that a QC brick will always pull maximum of what it is capable of? I always thought that it will only give what the device/cord can take.
I had a Nexus 6p before my Pixel XL, and it would not charge with A to C cord plugged in to a 1amp brick (the charging sign was just flickering on and off), but worked perfectly fine in a 2 amp brick.
Also, how come it is limited to 1amp, if regular usb a-to-a mini cords can easily 2 amps?
zanzabar
22
Sep 20, 2017
makatsThe USB spec only allows 5v1a over type a and b. Anything more is out of spec can be dangerous, but in the case of type a to c there needs to be a resistor in the cable that identifies it to be legacy so it won't do more than one amp, and qc 3 or lower can put voltage over data pins. If the type c port on the device has a built in hub or you have a cheap early qc brick it can change to qc mode and kill your device. Pulling extra power on a qc would not be an issue, but putting voltage on data pins is a problem.
Type c to c natively is 5v3a, and type c devices need to support USB pd as well to negotiate charging rates with in spec chargers and can do more, but legacy dumb type c native chargers are always 5v3a.
zanzabarZanzabar,
So I have tried your theory with my Samsung Note 8 on multiple chargers that all have QC3. I have the original USB-A (to be connected to the QC3 port on the charger) and the USB-C (to be connected to the phone). No matter what charger I use or cable that I use the phone gives me the following message "Android System Fast Charging". Now, the note 8 will only give this message if it is utilizing higher amperage in order to be able to charge fast. Testing this I have also plugged in my Note 8 to a 1 amp, 2 amp, and 2.4 amp USB-A charging ports and the Note 8 does not register them as fast charging.
The only time the Note 8 flagged the charging as "Android System Fast Charging" is the following. 1. Note 8 plugged in via USB-A to USB-C into a QC3 charging port. 2. Note 8 plugged in via USB-C to USB-C into a UCB-C charging port.
Also the stock charger that came with this phone have a single USB-A port on it and Samsung provided a USB-A to USB-C cable with it. When using the OEM charger it also registers as "Android System Fast Charging". Lastly next to the charging message that appears on the phone it shows how much time is needed to be at a full charge. This time was also appropriate depending on what amperage I had the phone plugged into. Meaning that when I used a more powerful charge the time needed to charge it went down.
Maybe what your explaining has been a problem in the past, or with certain phones but it is a non-issue with mine.
Cheers.
zanzabar
22
Apr 7, 2018
Tex-ArozziI dont use samsung phones, but if "Android System Fast Charging" is the same as rapidly charging (2A+ on stock android) then your a to c cable is out of spec. Get ampere ( https://play.google.com/store/apps/details?id=com.gombosdev.ampere ) and check what kind of amps it is pulling and what the max rating for the a to c cable is. Samsung does have their own fast charging spec that they share with apple, maybe that is making it do more than it should with an a to c, but the QC3 charger would not have that.
Ether way, the type C spec requires usb PD, and if on a to c you ever pull more than 1.5A that cable is dangerous to plug random things in with. And QC1-3 charges with a to c cables are dangerous since if you plug into something with a hub, and QC turns on (it sends voltage over data pins) it will kill things.
glennac
1363
Apr 8, 2018
zanzabarUnless you are dealing with a counterfeit device the smart circuitry in today’s device and chargers will always default to the lower powered standard. “For example, if you were to have the right cable to connect the latest and greatest smartphone with USB-C into an old, low-power, USB-A port, the phone would likely alert you to the low power and refuse to charge. The slower protocol always wins out.” (https://thewirecutter.com/blog/quick-charge-usb-c/) As for USB type C over a QuickCharge 3.0 connection, Qualcomm has addressed this specifically (in response to Google's Benson Leung‘s concerns): “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.” (https://www.androidcentral.com/qualcomm-addresses-usb-type-c-and-quick-charge-30-compatibility?amp) “It's also worth noting that both the phones and the chargers themselves have been UL listed and CE Mark certified as safe when used as directed.” (https://www.androidcentral.com/qualcomm-addresses-usb-type-c-and-quick-charge-30-compatibility?amp)
a.shafie
0
Apr 10, 2018
glennac "Unless you are dealing with a counterfeit device the smart circuitry in today’s device and chargers will always default to the lower powered standard" Exactly I once charged my HTC U11 with my razer stealth charger and everything was a-okay. Did the same thing with my nexus 6P when it was new and the board got "fried" both times were not intentional. This is the only drawback of using USB C imo. the razer charger outputs 20V 2.25A