I got a new battery for my iPod Classic and it would not charge. I
contacted the supplier, who said I needed to use a 1 amp charger and
not the 2.1 amp charger for my iPad Mini. It never occurred to me
that the amperage of the charger could be too high. This is not made
very clear by Apple. Does this mean an iPod Classic cannot be charged
using an integral charging socket on the wall? Will everyone (except
me) know this?

I thought USB was universal. Is it best after all to use the supplied
charger for each product as in the old days? Just interested.

Scott <newsgroups@gefion.myzen.co.uk> wrote:
> I got a new battery for my iPod Classic and it would not charge. I
> contacted the supplier, who said I needed to use a 1 amp charger and
> not the 2.1 amp charger for my iPad Mini. It never occurred to me
> that the amperage of the charger could be too high. This is not made
> very clear by Apple. Does this mean an iPod Classic cannot be charged
> using an integral charging socket on the wall? Will everyone (except
> me) know this?
>
> I thought USB was universal. Is it best after all to use the supplied
> charger for each product as in the old days? Just interested.
>

The charger current rating can’t be too high. The consuming circuit
determines how much current is required (for a given voltage before we go
down a rabbit hole of USB-C chargers that can negotiate a higher voltage to
push more amps).

Tweed <usenet.tweed@gmail.com> wrote:
> Scott <newsgroups@gefion.myzen.co.uk> wrote:
>> I got a new battery for my iPod Classic and it would not charge. I
>> contacted the supplier, who said I needed to use a 1 amp charger and
>> not the 2.1 amp charger for my iPad Mini. It never occurred to me
>> that the amperage of the charger could be too high. This is not made
>> very clear by Apple. Does this mean an iPod Classic cannot be charged
>> using an integral charging socket on the wall? Will everyone (except
>> me) know this?
>>
>> I thought USB was universal. Is it best after all to use the supplied
>> charger for each product as in the old days? Just interested.
>>
>
> The charger current rating can’t be too high. The consuming circuit
> determines how much current is required (for a given voltage before we go
> down a rabbit hole of USB-C chargers that can negotiate a higher voltage to
> push more amps).
>
>
>
It seems it’s more to do with the iPod requiring non standard voltage so
the usb data pins before it will accept charge. The iPad charger is not
providing this.

https://learn.adafruit.com/minty-boost/icharging

Allegedly this

https://www.amazon.com/Plugable-Universal-Charge-Only-Adapter-Android/dp/B00FA9GXKM/ref=sr_1_fkmr1_2

device overcomes the problem, and is confirmed by one of the user reviews.
Doesn’t seem to be immediately available via Amazon UK.

I also liked one of the users describing it as a USB condom.

Tweed wrote:

> I thought USB was universal.

I think Apple do "weird stuff" with networks of resistors on the data pins, to
indicate available current from charger to device, maybe new ipad chargers
confuse old ipods?

On Sat 26/03/2022 08:23, Andy Burns wrote:
> Tweed wrote:
>
>> I thought USB was universal.
>
> I think Apple do "weird stuff" with networks of resistors on the data
> pins, to indicate available current from charger to device, maybe new
> ipad chargers confuse old ipods?

ISTR my iPod Classic original charger was rated 5.1V or might even have
been 5.2V

On Sat, 26 Mar 2022 08:08:23 -0000 (UTC), Tweed
<usenet.tweed@gmail.com> wrote:

>>> I thought USB was universal. Is it best after all to use the supplied
>>> charger for each product as in the old days? Just interested.
>>>
[...]
>>
>It seems it’s more to do with the iPod requiring non standard voltage so
>the usb data pins before it will accept charge. The iPad charger is not
>providing this.
>
>https://learn.adafruit.com/minty-boost/icharging

A fascinating article, which makes me glad I've never had anything to
do with Apple products. They really do seem determined to make their
stuff as incompatible as possible with everything else so that you
have to buy their expensive accessories to make it work.

Rod.

Roderick Stewart <rjfs@escapetime.myzen.co.uk> wrote:
> On Sat, 26 Mar 2022 08:08:23 -0000 (UTC), Tweed
> <usenet.tweed@gmail.com> wrote:
>
>>>> I thought USB was universal. Is it best after all to use the supplied
>>>> charger for each product as in the old days? Just interested.
>>>>
> [...]
>>>
>> It seems it’s more to do with the iPod requiring non standard voltage so
>> the usb data pins before it will accept charge. The iPad charger is not
>> providing this.
>>
>> https://learn.adafruit.com/minty-boost/icharging
>
> A fascinating article, which makes me glad I've never had anything to
> do with Apple products. They really do seem determined to make their
> stuff as incompatible as possible with everything else so that you
> have to buy their expensive accessories to make it work.
>
> Rod.
>

Well not really. All the main manufactures got up to similar schemes when
it became apparent that the original USB power output was inadequate.
Eventually it has led to the USB-C power delivery standard where devices
can negotiate an increase in voltage and thus an increase in current.
Pretty much all mainstream devices are using or will use that standard.

On 26/03/2022 09:18, Roderick Stewart wrote:
> On Sat, 26 Mar 2022 08:08:23 -0000 (UTC), Tweed
> <usenet.tweed@gmail.com> wrote:
>
>>>> I thought USB was universal. Is it best after all to use the supplied
>>>> charger for each product as in the old days? Just interested.
>>>>
> [...]
>>>
>> It seems it’s more to do with the iPod requiring non standard voltage so
>> the usb data pins before it will accept charge. The iPad charger is not
>> providing this.
>>
>> https://learn.adafruit.com/minty-boost/icharging
>
> A fascinating article, which makes me glad I've never had anything to
> do with Apple products. They really do seem determined to make their
> stuff as incompatible as possible with everything else so that you
> have to buy their expensive accessories to make it work.
>
> Rod.

It isn't just Apple though. Many years ago I bought a (now obsolete)
Android 4 tablet. It came with a charger that plugged into the mains
and had a USB socket outlet. There was also a bespoke connector that
connected that USB socket to the tablet.

If I connected the bespoke lead to the tablet and the USB connector to a
computer, the computer saw the tablet as a couple of disc drives (main
memory and SD memory). But connecting the same lead to the power supply
it charged the tablet battery. According to the manual, the charging
voltage is 15V. So I have a mains wall wart with a USB socket that
delivers 15V. Anyone trying to reuse it as a general purpose USB
charger is going to fry whatever they intend to charge.

Jim

On Sat, 26 Mar 2022 14:07:25 +0000, Indy Jess John
<bathwatchdog@OMITTHISgooglemail.com> wrote:

>On 26/03/2022 09:18, Roderick Stewart wrote:
>> On Sat, 26 Mar 2022 08:08:23 -0000 (UTC), Tweed
>> <usenet.tweed@gmail.com> wrote:
>>
>>>>> I thought USB was universal. Is it best after all to use the supplied
>>>>> charger for each product as in the old days? Just interested.
>>>>>
>> [...]
>>>>
>>> It seems it’s more to do with the iPod requiring non standard voltage so
>>> the usb data pins before it will accept charge. The iPad charger is not
>>> providing this.
>>>
>>> https://learn.adafruit.com/minty-boost/icharging
>>
>> A fascinating article, which makes me glad I've never had anything to
>> do with Apple products. They really do seem determined to make their
>> stuff as incompatible as possible with everything else so that you
>> have to buy their expensive accessories to make it work.
>>
>> Rod.
>
>It isn't just Apple though. Many years ago I bought a (now obsolete)
>Android 4 tablet. It came with a charger that plugged into the mains
>and had a USB socket outlet. There was also a bespoke connector that
>connected that USB socket to the tablet.
>
>If I connected the bespoke lead to the tablet and the USB connector to a
>computer, the computer saw the tablet as a couple of disc drives (main
>memory and SD memory). But connecting the same lead to the power supply
>it charged the tablet battery. According to the manual, the charging
>voltage is 15V. So I have a mains wall wart with a USB socket that
>delivers 15V. Anyone trying to reuse it as a general purpose USB
>charger is going to fry whatever they intend to charge.
>
>Jim

At least we now have Qualcom Quickcharge 3, which is a sort of
standard as it seems to be used by several manufacturers (though not
Apple of course). A QC3 charger normally works like any other 5V
supply unless a compatible phone is plugged into it, whereupon the
phone uses the data lines to signal to the charger that it can accept
a higher volage. I've seen the voltage go to 9V when charging my
Samsung phone, and I understand that it can switch to higher voltages
depending on what's plugged into it, though I don't happen to possess
anything that wants more than 9V.

Curiously, a Chomebook that I recently acquired via Ebay came without
a charger and only had a USB-C port for charging, but wouldn't charge
from any of my existing chargers. So I got a charger advertised as
suitable for the Chromebook, and it works, but my USB meter registers
nothing at all from its USB-C output. I can only assume that it either
uses different pins (non-standard?) or it somehow has to detect the
presence of a bona fide Chromebook before it will produce any output.
I hope so, because the markings on the charger indicate it has a fixed
output of 20V and I don't think that would do a phone any good. I'm
not sure how it could initially detect a Chromebook with a completely
flat battery as mine was when I received it, if this depended on the
Chromebook generating an ident signal though.

Rod.

Roderick Stewart <rjfs@escapetime.myzen.co.uk> wrote:
> On Sat, 26 Mar 2022 14:07:25 +0000, Indy Jess John
> <bathwatchdog@OMITTHISgooglemail.com> wrote:
>
>> On 26/03/2022 09:18, Roderick Stewart wrote:
>>> On Sat, 26 Mar 2022 08:08:23 -0000 (UTC), Tweed
>>> <usenet.tweed@gmail.com> wrote:
>>>
>>>>>> I thought USB was universal. Is it best after all to use the supplied
>>>>>> charger for each product as in the old days? Just interested.
>>>>>>
>>> [...]
>>>>>
>>>> It seems it’s more to do with the iPod requiring non standard voltage so
>>>> the usb data pins before it will accept charge. The iPad charger is not
>>>> providing this.
>>>>
>>>> https://learn.adafruit.com/minty-boost/icharging
>>>
>>> A fascinating article, which makes me glad I've never had anything to
>>> do with Apple products. They really do seem determined to make their
>>> stuff as incompatible as possible with everything else so that you
>>> have to buy their expensive accessories to make it work.
>>>
>>> Rod.
>>
>> It isn't just Apple though. Many years ago I bought a (now obsolete)
>> Android 4 tablet. It came with a charger that plugged into the mains
>> and had a USB socket outlet. There was also a bespoke connector that
>> connected that USB socket to the tablet.
>>
>> If I connected the bespoke lead to the tablet and the USB connector to a
>> computer, the computer saw the tablet as a couple of disc drives (main
>> memory and SD memory). But connecting the same lead to the power supply
>> it charged the tablet battery. According to the manual, the charging
>> voltage is 15V. So I have a mains wall wart with a USB socket that
>> delivers 15V. Anyone trying to reuse it as a general purpose USB
>> charger is going to fry whatever they intend to charge.
>>
>> Jim
>
> At least we now have Qualcom Quickcharge 3, which is a sort of
> standard as it seems to be used by several manufacturers (though not
> Apple of course). A QC3 charger normally works like any other 5V
> supply unless a compatible phone is plugged into it, whereupon the
> phone uses the data lines to signal to the charger that it can accept
> a higher volage. I've seen the voltage go to 9V when charging my
> Samsung phone, and I understand that it can switch to higher voltages
> depending on what's plugged into it, though I don't happen to possess
> anything that wants more than 9V.
>
> Curiously, a Chomebook that I recently acquired via Ebay came without
> a charger and only had a USB-C port for charging, but wouldn't charge
> from any of my existing chargers. So I got a charger advertised as
> suitable for the Chromebook, and it works, but my USB meter registers
> nothing at all from its USB-C output. I can only assume that it either
> uses different pins (non-standard?) or it somehow has to detect the
> presence of a bona fide Chromebook before it will produce any output.
> I hope so, because the markings on the charger indicate it has a fixed
> output of 20V and I don't think that would do a phone any good. I'm
> not sure how it could initially detect a Chromebook with a completely
> flat battery as mine was when I received it, if this depended on the
> Chromebook generating an ident signal though.
>
> Rod.
>

Your chrome book will be using the USB-C power delivery standard. In simple
terms the link starts at a safe 5V and the charger and device negotiate a
safe higher voltage.

On 26/03/2022 12:20, Tweed wrote:
> Roderick Stewart <rjfs@escapetime.myzen.co.uk> wrote:
>> On Sat, 26 Mar 2022 08:08:23 -0000 (UTC), Tweed
>> <usenet.tweed@gmail.com> wrote:
>>
>>>>> I thought USB was universal. Is it best after all to use the supplied
>>>>> charger for each product as in the old days? Just interested.
>>>>>
>> [...]
>>>>
>>> It seems it’s more to do with the iPod requiring non standard voltage so
>>> the usb data pins before it will accept charge. The iPad charger is not
>>> providing this.
>>>
>>> https://learn.adafruit.com/minty-boost/icharging
>>
>> A fascinating article, which makes me glad I've never had anything to
>> do with Apple products. They really do seem determined to make their
>> stuff as incompatible as possible with everything else so that you
>> have to buy their expensive accessories to make it work.
> Well not really. All the main manufactures got up to similar schemes when
> it became apparent that the original USB power output was inadequate.
> Eventually it has led to the USB-C power delivery standard where devices
> can negotiate an increase in voltage and thus an increase in current.
> Pretty much all mainstream devices are using or will use that standard.

You don't need a higher voltage to take more current.

--
Max Demian

On Sat, 26 Mar 2022 08:25:34 +0000, Woody <harrogate3@ntlworld.com>
wrote:

>On Sat 26/03/2022 08:23, Andy Burns wrote:
>> Tweed wrote:
>>
>>> I thought USB was universal.
>>
>> I think Apple do "weird stuff" with networks of resistors on the data
>> pins, to indicate available current from charger to device, maybe new
>> ipad chargers confuse old ipods?
>
>ISTR my iPod Classic original charger was rated 5.1V or might even have
>been 5.2V

So you you think a voltage mismatch is more likely to be the issue
than a charger with too high an amperage? I still don't see why an
Apple iPod won't charge with an Apple charger, when both are USB.

Scott wrote:

> you you think a voltage mismatch is more likely to be the issue
> than a charger with too high an amperage?

As others have explained, the maximum current that can be supplied is a feature
of the charger, the actual current that will be taken is a feature of the device
being charged.

On Sun, 27 Mar 2022 12:01:10 +0100, Andy Burns <usenet@andyburns.uk>
wrote:

>Scott wrote:
>
>> you you think a voltage mismatch is more likely to be the issue
>> than a charger with too high an amperage?
>
>As others have explained, the maximum current that can be supplied is a feature
>of the charger, the actual current that will be taken is a feature of the device
>being charged.

So you say, but when I tried to charge the device with a 2.1A charger,
it would not charge. The charger is tested and working. When I tried
to charge the iPod with a 1A charger, it charged okay.

I assumed exactly as you say, so I remain puzzled.

On 27/03/2022 12:13, Scott wrote:
> So you say, but when I tried to charge the device with a 2.1A charger,
> it would not charge. The charger is tested and working. When I tried
> to charge the iPod with a 1A charger, it charged okay.

Without some signalling to the charger, a device shouldn't try to draw
more than 100mA. It is possible that 100mA doesn't look like charging,
and it probably won't be if the device is active. It could also be that
the USB default is considered to be too inadequate that the device
doesn't even attempt to limit itself to 100mA, but prefers to ignore
something that doesn't offer the current it wants.

On 27/03/2022 11:20, Max Demian wrote:
> You don't need a higher voltage to take more current.

Yes and no. You need a higher voltage, on the wire, to push more
current into the battery, but the current on the wire is still
constrained to avoid overheating.

There is going to be a DC to DC convertor in the phone, which converts
high voltage, medium current, into battery voltage and high current.

I think the current on the wire can go up a bit, as you can accept more
voltage drop in the wire, as it is a smaller proportion of the total
voltage.

On Sun, 27 Mar 2022 12:28:48 +0100, David Woolley
<david@ex.djwhome.demon.invalid> wrote:

>On 27/03/2022 12:13, Scott wrote:
>> So you say, but when I tried to charge the device with a 2.1A charger,
>> it would not charge. The charger is tested and working. When I tried
>> to charge the iPod with a 1A charger, it charged okay.
>
>Without some signalling to the charger, a device shouldn't try to draw
>more than 100mA. It is possible that 100mA doesn't look like charging,
>and it probably won't be if the device is active. It could also be that
>the USB default is considered to be too inadequate that the device
>doesn't even attempt to limit itself to 100mA, but prefers to ignore
>something that doesn't offer the current it wants.

So it is the case that the device won't charge because the amperage of
the charger is too high? This seems illlogical and no-one believes
me, but I can assure you this is what happened and my puzzlement
remains.

David Woolley <david@ex.djwhome.demon.invalid> wrote:
> On 27/03/2022 11:20, Max Demian wrote:
>> You don't need a higher voltage to take more current.
>
> Yes and no. You need a higher voltage, on the wire, to push more
> current into the battery, but the current on the wire is still
> constrained to avoid overheating.
>
> There is going to be a DC to DC convertor in the phone, which converts
> high voltage, medium current, into battery voltage and high current.
>
> I think the current on the wire can go up a bit, as you can accept more
> voltage drop in the wire, as it is a smaller proportion of the total
> voltage.
>

It’s not just for phones. The USB-C power delivery standard is also used by
laptops. They certainly need more volts.

Scott <newsgroups@gefion.myzen.co.uk> wrote:
> On Sun, 27 Mar 2022 12:28:48 +0100, David Woolley
> <david@ex.djwhome.demon.invalid> wrote:
>
>> On 27/03/2022 12:13, Scott wrote:
>>> So you say, but when I tried to charge the device with a 2.1A charger,
>>> it would not charge. The charger is tested and working. When I tried
>>> to charge the iPod with a 1A charger, it charged okay.
>>
>> Without some signalling to the charger, a device shouldn't try to draw
>> more than 100mA. It is possible that 100mA doesn't look like charging,
>> and it probably won't be if the device is active. It could also be that
>> the USB default is considered to be too inadequate that the device
>> doesn't even attempt to limit itself to 100mA, but prefers to ignore
>> something that doesn't offer the current it wants.
>
> So it is the case that the device won't charge because the amperage of
> the charger is too high? This seems illlogical and no-one believes
> me, but I can assure you this is what happened and my puzzlement
> remains.
>

Your iPod is looking for a certain combination of signalling
resistors/voltages on the USB data pins. That’s not provided by your higher
power charger, as that’s using those pins to advertise it can do 2A. Your
iPad classic is too old to understand this latter signalling and decides
not to enable its charge circuit.

The iPod classic was designed in the relative early days of using usb as a
charging method as opposed to its primary design intent a data bus. People
like to castigate Apple, but their laptops were some of the first to market
to use USB-C as a means of powering the device. It’s relatively common
across all new laptops now.

On 27/03/2022 12:34, Scott wrote:
> So it is the case that the device won't charge because the amperage of
> the charger is too high?

No it is because it doesn't see the signalling that indicates that it is
capable of more than 100mA, or given that there probably is a reasonably
full USB interface, doesn't know how to negotiate beyond the original
absolute limit of 500mA.

The charger it expects, probably abuses the signalling leads to use
analogue means of indicating that it can provide more than the USB
standard allows, but the current generation of chargers use digital
means, and won't provide the analogue indication the device is
expecting. I'd expect the analogue indication to compromise the use of
the data wires for real digital data, so I suspect that a charger can't
appear to both.

Scott wrote:

> Andy Burns wrote:
>
>> As others have explained, the maximum current that can be supplied is a feature
>> of the charger, the actual current that will be taken is a feature of the device
>> being charged.
>
> So you say, but when I tried to charge the device with a 2.1A charger,
> it would not charge.

I believe you, but it's not because it's a 2.1A charger, it's because it isn't
an iPod charger, so doesn't know the 'secret handshake'

Andy Burns <usenet@andyburns.uk> wrote:
> Scott wrote:
>
>> Andy Burns wrote:
>>
>>> As others have explained, the maximum current that can be supplied is a feature
>>> of the charger, the actual current that will be taken is a feature of the device
>>> being charged.
>>
>> So you say, but when I tried to charge the device with a 2.1A charger,
>> it would not charge.
>
> I believe you, but it's not because it's a 2.1A charger, it's because it isn't
> an iPod charger, so doesn't know the 'secret handshake'
>

I’ve never considered the Masonic charger before…. :)

On Sun, 27 Mar 2022 13:55:53 +0100, David Woolley
<david@ex.djwhome.demon.invalid> wrote:

>On 27/03/2022 12:34, Scott wrote:
>> So it is the case that the device won't charge because the amperage of
>> the charger is too high?
>
>No it is because it doesn't see the signalling that indicates that it is
>capable of more than 100mA, or given that there probably is a reasonably
>full USB interface, doesn't know how to negotiate beyond the original
>absolute limit of 500mA.

I'm missing something. Why does an iPod need more than 100mA? Surely
it should charge with what it gets and just take longer.
>
>The charger it expects, probably abuses the signalling leads to use
>analogue means of indicating that it can provide more than the USB
>standard allows, but the current generation of chargers use digital
>means, and won't provide the analogue indication the device is
>expecting. I'd expect the analogue indication to compromise the use of
>the data wires for real digital data, so I suspect that a charger can't
>appear to both.

Not the amperage then (as I was told by the battery man) but just that
newer chargers are not compatible with older equipment. I don't
remember seeing that on the Apple box when I bought the new charger
but maybe I did not look closely enough.

On 27/03/2022 18:00, Scott wrote:
> Why does an iPod need more than 100mA? Surely
> it should charge with what it gets and just take longer.

What it gets could be anything up to what it tries to take, but that
might overheat the power supply or the USB interface in the PC it is
charging from, or might cause the USB hub to current limit causing other
devices on the same hub fail through under-voltage.

On Sun, 27 Mar 2022 10:17:29 -0000 (UTC), Tweed
<usenet.tweed@gmail.com> wrote:

>Roderick Stewart <rjfs@escapetime.myzen.co.uk> wrote:
>> On Sat, 26 Mar 2022 14:07:25 +0000, Indy Jess John
>> <bathwatchdog@OMITTHISgooglemail.com> wrote:
>>
>>> On 26/03/2022 09:18, Roderick Stewart wrote:
>>>> On Sat, 26 Mar 2022 08:08:23 -0000 (UTC), Tweed
>>>> <usenet.tweed@gmail.com> wrote:
>>>>
>>>>>>> I thought USB was universal. Is it best after all to use the supplied
>>>>>>> charger for each product as in the old days? Just interested.
>>>>>>>
>>>> [...]
>>>>>>
>>>>> It seems it?s more to do with the iPod requiring non standard voltage so
>>>>> the usb data pins before it will accept charge. The iPad charger is not
>>>>> providing this.
>>>>>
>>>>> https://learn.adafruit.com/minty-boost/icharging
>>>>
>>>> A fascinating article, which makes me glad I've never had anything to
>>>> do with Apple products. They really do seem determined to make their
>>>> stuff as incompatible as possible with everything else so that you
>>>> have to buy their expensive accessories to make it work.
>>>>
>>>> Rod.
>>>
>>> It isn't just Apple though. Many years ago I bought a (now obsolete)
>>> Android 4 tablet. It came with a charger that plugged into the mains
>>> and had a USB socket outlet. There was also a bespoke connector that
>>> connected that USB socket to the tablet.
>>>
>>> If I connected the bespoke lead to the tablet and the USB connector to a
>>> computer, the computer saw the tablet as a couple of disc drives (main
>>> memory and SD memory). But connecting the same lead to the power supply
>>> it charged the tablet battery. According to the manual, the charging
>>> voltage is 15V. So I have a mains wall wart with a USB socket that
>>> delivers 15V. Anyone trying to reuse it as a general purpose USB
>>> charger is going to fry whatever they intend to charge.
>>>
>>> Jim
>>
>> At least we now have Qualcom Quickcharge 3, which is a sort of
>> standard as it seems to be used by several manufacturers (though not
>> Apple of course). A QC3 charger normally works like any other 5V
>> supply unless a compatible phone is plugged into it, whereupon the
>> phone uses the data lines to signal to the charger that it can accept
>> a higher volage. I've seen the voltage go to 9V when charging my
>> Samsung phone, and I understand that it can switch to higher voltages
>> depending on what's plugged into it, though I don't happen to possess
>> anything that wants more than 9V.
>>
>> Curiously, a Chomebook that I recently acquired via Ebay came without
>> a charger and only had a USB-C port for charging, but wouldn't charge
>> from any of my existing chargers. So I got a charger advertised as
>> suitable for the Chromebook, and it works, but my USB meter registers
>> nothing at all from its USB-C output. I can only assume that it either
>> uses different pins (non-standard?) or it somehow has to detect the
>> presence of a bona fide Chromebook before it will produce any output.
>> I hope so, because the markings on the charger indicate it has a fixed
>> output of 20V and I don't think that would do a phone any good. I'm
>> not sure how it could initially detect a Chromebook with a completely
>> flat battery as mine was when I received it, if this depended on the
>> Chromebook generating an ident signal though.
>>
>> Rod.
>>
>
>Your chrome book will be using the USB-C power delivery standard. In simple
>terms the link starts at a safe 5V and the charger and device negotiate a
>safe higher voltage.

Why does my USB meter not show anything then? It shows the 5V from any
other USB charger, but with the Chromebook charger it shows nothing at
all, as its screen doesn't even light up. If the charger was producing
5V I would expect it to show on the meter.

Rod.