Question about Fast adaptive charging

[dacflyer]

I bought some of these fast adaptive charging modules from ICSTATION
USB Universal Protocal QC 3.0

http://www.icstation.com/buck-converter ... 13287.html

These don't seem to be working with any of the samsung tablets I have, The tablets always say to use the original charger for fast charging..
so when using these modules, they won't fast charge.

Is there anything i could do make these work for my tablets?
what is special in the original charger that it recognizes ?

[Janitor Tzap]

Here's some info about the different fast charging methods that are being used currently.
https://www.androidauthority.com/fast-c ... ed-889780/
Unfortunately they don't go into the circuitry that the different manufactures use.


Signed: Janitor Tzap

[dacflyer]

ya, i saw this earlier as well, wasn't very helpful.
I tried emailing the MFG. for the modules i have, but of course, no replies.

[Janitor Tzap]

I came across this PDF file; https://www.onsemi.com/pub/Collateral/AN-8209.pdf.pdf


Signed: Janitor Tzap

[haklesup]

I use one of those USB Voltage and Current measurement dongles. You can place it between any device and charger on the USB cable and measure actual charge current and voltage. I have been known to sample several wall warts and chose the one with the highest charge rate at any given time.

One thing I noticed lately is that the AC voltage can effect the DC output somewhat, A charger that normally gets me 1.1A charge current wouldn't go above 400mA last week when I was visiting family but the same charger and device got back to 1.1A when I got home again. I didn't record the DC voltage but I recall it seemed higher than nominal for that charger which is counterintuitive that the charge rate went down. Apparently the battery management S/W in the device (A Samsung 10" Tablet) was doing something to keep it cool.

The Samsung 2A chargers work pretty well on most devices but some 1A chargers were a little low on the 5V target (Nominal is in the 5.1V to 5.25V range)

There are many of these dongles and the prices are low, pair it up with a USB resistive load and you can measure discharge performance as well.

I scanned the article link, I understand fast charging but did not catch the definition of what makes it "adaptive" I think it just means the voltage is a little variable to maximize current into a software managed charging port.

[dacflyer]

ok,, so i know that the phone / tablet dictates how the charger will put out. But the chargers i have were supposed to work with such items, The video even demonstrated that.. but the guy was using a device to trigger the charging rate. which leads me to believe now, that the device is a farce..
either way..i haven't found them to work with anything i have..only a slow charge.

[Janitor Tzap]

Caveat emptor {Buyer Beware}.

There are a lot of these chargers showing up now, sad too say.

I came across a video on youtube, where a guy buys what he thinks is the original Samsung Fast charger for his phone for cheap.
But after it burned out. He takes it apart to find that it is nothing more than some badly made Chinese knock-off.
https://www.youtube.com/watch?v=eCDKnQsCvSQ


Signed: Janitor Tzap

[dyarker]

Maybe the "original" was a bad Chinese knock-off! Else why is everybody buying replacements?

[haklesup]

We buy replacements because we lose them or need spares for travel or just different rooms. Since the Koreans don't particularly get along with the Chinese, I can't imagine an authorized Samsung product not make in Korea. They make the empty statement to use the charger that came with it because that's the only one they have any idea how it works with the device. The adaptive chargers seem to act a little like a current source with a 5V offset, so at no load they have a nominal voltage of about 5.25V but under load, they adjust V like a current source to supply the charge voltage the device likes to get the fastest rate the device allows. Some devices do a better job at managing that than others, there have been constant improvements in battery management chips and software in every generation of phones and other devices. As far as I know, no device communicates digitally with a charger to command it.

[dyarker]

You lose them often enough to create an after-market?

Since the Koreans don't particularly get along with the Chinese, I can't imagine an authorized Samsung product not make in Korea.

Then delete word "Chinese" from above, and leave "knock-off".

As far as I know, no device communicates digitally with a charger to command it.

Then problem in original post does not exist. "Command" might be too strong, USB hosts communicate with devices to negotiate load current range, why wouldn't a host negotiate with charger about charge rate. No negotiation would mean one rate always like from a simple power supply. Oh look, that does sound like original post! Maybe Samsung has gone proprietary in protocol to stop their devices being damaged by knock-off chargers.

[dacflyer]

dyarker >> i buy them to power projects.
But I'm looking to try and see if i can modify the units i have now, but it doesn't look like it

[dyarker]

What you said in post 1 -

Is there anything i could do make these work for my tablets?

Above applies.
In last post -

i buy them to power projects.

Won't work unless building a USB project. Use a switching mode regulated supply.

Cheers,

[dacflyer]

I'm looking to make the modules work with my samsung,, but i was also answering the other question of what Dyarker asked.
Why is everybody buying replacements. the modules i am hoping to use for anything. mainly a portable battery powered charger, kind of like a battery bank. but apparently the modules i got won't work for my needs. So i gotta start looking elsewhere.

[haklesup]

The Negotiation between charger and device is all Analog. A managed device can throttle the charge current to maintain safe charge temperature and prolong life according to the manufacturers firmware. The adaptive charger responds to the change in [device] charge current [limit] by adjusting the output voltage accordingly. An old fashion Linear power supply would probably do this organically but the new switcher designs need to have a little help. For example if they held fixed at exactly 5.25V for all load currents, there may be times when that results in too large a voltage drop across a regulator resulting in excess heat and inefficiency.

I have not yet put my finger on what circuitry or spec qualifies the descriptor "Adaptive", it may be a marketing term with unclear technical meaning. I think I am fairly close though.

if not for replacement of lost supplies, some people might be replacing linear transformer style wall warts which are traditionally less efficient than switcher (SMPS) designs and also larger.

My older acer supply works equally well as the Samsung charger for any device I have tried as do most generic 1A and 2A chargers. Brand matching is just a CYA tactic when writing the manual.

[dacflyer]

gotchya, I have yet to find anything other than the original plug in charger to kick in the fast charging, anything else i use / try, just results in the pop up screen saying, slow charging. Use the original charger to activate fast charging.
I mainly want something to use in a DC world, Battery bank or in car, etc.
the units i bought, were said to do this,, but they don't. so i gotta find something.