Puhelinvalmistajat markkinoivat uutuuksiaan usein hurjilla pikalataustehoilla, jotka mahdollistavat latauksen vain kymmenissä minuuteissa. Moni kuitenkin saattaa pettyä, kun kotona lataus onkin odotettua hitaampaa.

Syynä voi olla latausjohto. Suuritehoinen lataus onnistuu vain soveltuvalla usb-c-kaapelilla. Valitettavasti usb-c-kaapelista ei aina välttämättä selviä, kuinka paljon tehoa ja dataa ne pystyvät siirtämään. Myyntipakkauksessa tiedot ovat näkyvillä ja joissain tapauksissa kaapeliin on myös kiinnitetty tiedot sisältävä tarra.

Yksinkertaisin tapaus on joku laptopin USB laturi joka kykenee antamaan yli 100 W käyttäen suurempaa kuin 5V jännitettä. Kytkettäessä laturi vanhanaikaiseen 5V laitteeseen jännite jää tuohon 5V tasoon ja lopuksi ladattava laite päättelee laturin datapinnien tilan perusteella voiko ladata 500mA, 1.5A vai 3 A virralla. Ladattava laite siis päättää millä teholla lataus tapahtuu. USB A ja B liittimissä jos datapinnit ovat oikosulussa se kertoo ladattavalle laitteelle että voi imaista yli 500 mA virran. On myös muita tapoja kertoa tuo virran antokyky.

Kytkettäessä sama laturi laptoppiin USB-C liittimessä olevilla CC pinneillä laitteet kommunikoivat ja päättävät nostaa jännitteen ylemmäs jolloin suurempi teho, esimerkiksi 100W toteutuu. Laturi siis kertoo että se pystyy antamaan esimerkiksi 20V ja 5A ja samalla ladattava laite kertoo että 20 V on just fine hänelle eli antaa tulla vain. Lopuksi ladattava laite pyrkii nostamaan latausvirran 5A tasolle tosin se ei aina toteudu. Toteutuneeseen latausvirtaan vaikuttaa akun tila, lämpötila yms.

Vesa Eskola Asiahan ei valitettavasti ole noin. Mitä vain laitetta voi YRITTÄÄ ladata millä vain USB-C laturilla, mutta ei se tarkoita, että lataisi. Kaikissa latureissa ja USB-C laitteissa on piiri, joka kertoo toiselle osapuolelle, mitä jännitettä ja virtaa laite voi käyttää ja jos ei löydy yhteistä, ei lataaminen onnistu. Esimerkiksi simppeli puhelimen laturi voi antaa vain 5 V ja 12 V ja läppäri vaatii min. 20 V jännitteen, ei lataaminen onnistu. Ja vaikka oikea jännite löytyisi, voi homma tyssätä myös virran syötön riittämättömyyteen. Kaikki eivät siis toimi keskenään, se on väärää tietoa. Mitään vahinkoa ei tapahdu kylläkään, se on standardissa varmistettu

Jarno Vilen Jokainen standardia noudattava laturi antaa 5V/500 mA. Tietenkään laptop joka lataa vain 20V jännitteellä ei lataannu 5V jänniteellä. En niin ole väittänytkään, mitään ei kuitenkaan hajoa. No ehkä toi sanamuoto oli väärä,voi ladata pitäs olla voi yrittää ladata. Samoin joku älykännykkä ollessaan käytössä kuluttaa yli 500mA, jos laturi antaa vain 5V/500mA eli vain vbus näkyy laitteelle, akku kuluu mutta hitaammin kuin ilman laturia.

On myös latureita jotka eivät noudata standardia. Lueppas vielä kerran se kirjoittamani teksti ja kerro mikä kohta siinä on väärin.

Kaikissa usb-c laitteissa ei ole piiriä joka kommunikoi cc pinnien kautta, yksinkertaisimmissa on vastukset (Rp) jotka määrittävät miten paljon 5V jännitettä saa kuormittaa. 22k Rp -> 1.5A@5V ja vastaavasti 10k -> 3A. Kommunikoiva piiri tavitaan vain latureissa jotka nostavat jännitteen yli 5V tasolle power negotian käsittelyn jälkeen.

Olihan se mullekin pettymys kun kännykän 66W laturi ei lataa lainkaan thinkpadiä, syynä on laturin kyvyttömyys nostaa jännite tarpeeksi suureksi…silloin kun ne neuvottelevat voiko jännitteen nostaa laturi sanoo ettei onnistu.

Vesa Eskola “Millä tahansa USB laitteella voi ladata mitä vain.”. Tämä on väärin.

Vesa Eskola Ei tässä nyt mitään sen isompaa ole kuin se, että on hyvä, että ihmiset ymmärtävät, että kaikilla latureilla ja laitteilla EI VOI ladata kaikkia USB-C laitteita. Jos lähtee reissuun yhdellä laturilla, ei se takaa, että kaikki laitteet latautuvat. Eli se kannattaa varmistaa ensin. Tämä oli tarkennukseni syy, ei sinun arvosteleminen. Miten suomalaiset ottavat heti itseensä tällaisista? Heikolla täytyy itsetunnon olla.

https://www.facebook.com/share/p/1EjLFrD2mA/

Does a USB-A connector even have the pins required for negotiating power delivery (PD)? I know it can supply at least 5V voltage, but I’m not interested in that; I’m interested in power delivery standard with much higher voltages.

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If one were to look long and hard enough for the specifications on USB Power Delivery version 1.0 then you will see a means by which a compliant source and sink could negotiate up to 20 volts at 5 amps on a USB-A connector. There were no extra pins for this negotiation, the communications was by BFSK modulated signals sent on the Vbus and Vgnd lines.

Use of USB-PD on USB-A was short lived, and I am not aware of seeing any devices that operated in this manner. One issue I heard was that the communication was not well isolated and so one device could have this power negotiation induced onto an adjacent port and that device would see it’s voltage change even though it made no such request. This could damage hardware. Another problem was that the cables would have to be certified for this higher voltages and current, meaning the cables would have to be built for this as well have a means for the USB controller to know that the cables met the spec.

USB-PD 1.0 was not required for USB-A but it was required for USB-C, and that likely affected adoption. USB-C had a different means to handle PD negotiation, the Configuration Channel, which used a different protocol called BMC. USB-C could optionally support BFSK on Vbus for communication with USB-A ports which meant that to assure compatibility the cables would have to translate the PD negotiation, or do no PD negotiation at all and supply only the default 5 volts.

At the same time USB-PD 1.0 was introduced so where a couple competing systems for negotiating power over USB-A. USB-PD was a bit late to the game and so QuickCharge and others took over that space. I believe that they simply negotiated the power over the USB D+/D- lines. This violated the USB spec, or perhaps not, and because it was in a grey area the USB specification enforcers could not, or would not, do much about it.

Not many people cared much of USB-PD until version 2.0 and it was required for USB-C. USB-PD v1.0 was technically supported but not much people even cared.

There was a power delivery extension to USB 2.0, however that was essentially just allowing USB 2.0 ports to provide a higher current (>2A), but still not exceeding 5V. That was possible based on using resistor values on the data lines to select power delivery current levels.

As far as I’m aware using USB-A connectors to deliver (or select) higher voltages is not possible under the official USB standard, power delivery or otherwise. To do so requires some other proprietary technology that deviates from the standard.

USB PD 2.0 had defined “PD Standard-A” and “PD Standard-B” connectors. These are of historical significance only, as USB PD standardization has basically washed their hands off type-A and type-B connectors, cables, etc.

The idea was that there could be “PD Capable” A-B cables, rated for 3A VBUS current.

These connectors did not have CC-like pins. The PD communications were supposed to be carried out via FM modulation on VBUS. That was a neat idea, but stillborn idea, since nobody apparently cared enough to push it on the market.

“There’s the earth wire. Ooh, it’s an empty wire!”

In this video, Gokul shows you how to check the power output of a USB port on Windows 11. He walks you through two methods: one using the Device Manager and the other using a third-party application called USBDeview. Follow along to learn how to monitor the power state of your USB ports and ensure they’re functioning optimally.

Using USB for powering devices is wonderful, as it frees us from a tangle of incompatible barrel & TRS connectors, not to mention a veritable gaggle of proprietary power connectors. The unfortunate side-effect of this is that the obvious thing to do with power connectors is to introduce splitters, which can backfire horribly, especially since USB-C and USB Power Delivery (USB-PD) were introduced. The [Quiescent Current] channel on YouTube recently went over the ways in which these handy gadgets can literally turn your USB-powered devices into a smoldering pile of ashes.

Much like Qualcomm’s Quick Charge protocols, USB-PD negotiates higher voltages with the power supply, after which this same voltage will be provided to any device that’s tapped into the power supply lines of the USB connector. Since USB-C has now also taken over duties like analog audio jacks, this has increased the demand for splitters, but these introduce many risks.

Why USB-C multiport adapters can be dangerous
https://www.youtube.com/watch?v=lvnoz5uaTwE

USB-C splitters or extensions can be convenient, but may also break your devices if used in the wrong combination. This can be annoying, but worst case dangerous if something gets hot or catches fire.

Comments:

Completely correct that they CAN be dangerous. They can also not be dangerous. I have a few of these adapters, that serves the same purpose as yours. Except the ones I have are a bit bigger, because they each have a built-in USB hub, that provides USB 3.0 or 3.1 speed on the secondary port. The primary port is the passthrough port for charging (up to 20V/100W on mine). The secondary port is a regular USB-C or USB-A port with just 5V output, because it goes through a voltage regulator either inside the USB hub chip or a separate one. I have one connected to my laptop at home, which provides power to my laptop, but the other USB port is connected to an USB-C 2.5G ethernet dongle.

With the iPhone 15 coming out soon I’m so ready to embrace the USB-C life and throw all my lightning cables in the big old garbaggio. My car only comes with one single USB-A port in the centre console box and the cigarette lighter outlet is completely broken. I was thinking about picking up one of those split USB-C cables with a USBA on one end and three USB-Cs on the other as this would finally solve arguments over who gets to charge their phone in my car. But after doing some research I’ve heard some questionable things about the safety of these cables. I’m willing to bet you all know more about this than me so I’m interested to hear your thoughts

https://www.reddit.com/r/UsbCHardware/comments/16hzjt0/are_threeway_split_cables_safe_to_use_for_phone/

Most of you have encountered or have used one of those smart looking 3in1 or 4in1 USB ports charging cables. Those who have one of these is happily using it and even brag in front of his friends about having such a smart gadget. However, why those cables are not widely available and not offered by the big brands? Are they safe to use? Are there any limitations or things to bear in mind when purchasing one of these?

So what is multi charging cable?

For those of you who are not quite aware – multi charging cables are special cables which have the standard USB-A (the one available on most of the computers today) input on one side and multiple different outputs on the other side. Those could be micro USB (used mainly by Android devices and some other accessories), 8-pin Lightning (a.k.a. Apple plug, designed and patented by Apple for iPhone, iPad, iPod devices), USB-C (a.k.a. USB Type-C, the new advanced version of the USB A port used on the latest mobile devices). The reasons of having one input and multiple outputs are two:

You can use a single cable to charge almost any mobile device out there
You can charge multiple devices at a time with just a single cable and charger

This sounds very convenient, right? It gets you want to ask why are not we all using only multi charging cables. You will need a little more details so you can understand the answ

Mixing different standards into the same product is not a trivial task. One of the reasons why none of the leading smartphone vendors have desire to release such a product. They do not want to be sued or promote standards not available to them.

The communication between devices and chargers is handled differently for each standard, which makes them incompatible with each other. For instance one of the standards called Qualcomm Quick Charge is using the data wires in the cable to send signals. USB Power Delivery, which we mentioned already, is using the power wires for both transmitting power and exchanging signals to control the charging speed.

Challenges and limitations

When comes to using a triple charging cable with a fast charging device and charger there is one very important fact to consider. The higher voltage or amperage requested by the device is not only delivered to its output but also to the other outputs of the cable. If you connect a different device to one of the other ports, it may not be capable of consuming higher than the standard amount of power. This can lead to damaging the third device or even cause its battery to explode. Even if you connect multiple devices which support fast charging it is not clear which one will take over the control of the charger which automatically put the other device at risk for receiving more power depending on its battery percentage. The bottom line is that there is no safe way of using fast charging devices with multi charging cables.

To understand the other reason you first need to know what is Fast Charging. That is another feature that came up when the batteries of the mobile devices became larger hence time to charge was jumped to several hours. Fast charging is a technology to increase the power transferred from your charger to your mobile device. That is done by increasing the charging voltage or amperage or both. For example the standard charging uses 5V voltage and up to 2.4A amperage which delivers up to 12W of power. USB Power Delivery (one of the fast charging technologies) can increase the voltage up to 20V and the amperage up to 5A for a total of 100W of power.

This is the reason why the safe multi charging cables have the fast charging technologies disabled. This requires the data wires of all the Micro USB and USB C plugs to be removed. As explained above removing the data connection disables the Qualcomm QC capability. The only plug, which could keep its data wires, is the 8-Pin Lightning as Apple devices as they are not used by fast charging technology.

This is the limitation of the multi charging cables. You will not be able to use fast charging technology and you will not be able to use them to sync your device unless you are with iPhone or iPad. There are some multi charging cables on the market which support data on all outputs but I would highly recommend you to stay away. You cannot be sure, when someone will connect a fast charging device together with another one and cause a disaster.

Is it worthwhile using multi charging cables then?

If you consider carrying a single cable for all your devices more important than the fast charging, then the answer is yes. I would actually recommend you to use normal charging as often as possible. It is not well known fact that fast charging puts a lot of stress on the battery and reduces battery life over time. Using slow charging most of the times can give you one or two additional years with your favorite smartphone.

Does USB charging amperage drop with multi-output cables? I have a cable that can charge one mini USB device, one USB-C device, and two Apple Lightening devices at the same time. Do they all get the same 2.1 amps? Or are they have reduced charging?

USB charging amperage can indeed drop when using multi-output charging cables. The total available current from the power source is divided between the connected devices.

With a multi-output cable that can charge one mini USB, one USB-C, and two Lightning devices simultaneously, the 2.1A total current will be shared among the connected devices. Typically, in these situations, each port will provide reduced amperage, often around 1A or less per port.

The exact current available per port depends on the cable’s design and the power source it is connected to. Higher-quality cables and power adapters may be able to provide closer to full 2.1A per port, but it is common for the amperage to be reduced when multiple devices are charged simultaneously. The user should consult the cable’s specifications or manufacturer information to understand the expected current delivery per port under multi-device charging conditions.