Re: Specs on Nokia phone chargers

"Bruce" <nomail@bigpond.net.au> wrote in message
news:ssWVd.183735$K7.133083@news-server.bigpond.net.au...
> 5.7V 800mA
> same as AC charger.
> "no name" <noemail> wrote in message news:42283230$1@dnews.tpgi.com.au...
> | You know the stock standard nokia car charger, the one that works on
> pretty
> | much all Nokia phone's, does anybody know the output on this? i assume
> it
> | pushes out 12V, how many amp?
> |


Mine is 3.7V, 355mA

Uncle Bully wrote:
> "Bruce" <nomail@bigpond.net.au> wrote in message
> news:ssWVd.183735$K7.133083@news-server.bigpond.net.au...
>
>>5.7V 800mA
>>same as AC charger.
>>"no name" <noemail> wrote in message news:42283230$1@dnews.tpgi.com.au...
>>| You know the stock standard nokia car charger, the one that works on
>>pretty
>>| much all Nokia phone's, does anybody know the output on this? i assume
>>it
>>| pushes out 12V, how many amp?
>>|
>
>
>
> Mine is 3.7V, 355mA

Did you read that off the standard ACP-7A AC charger?

That's a nominal figure, as the ACP-7A is not regulated
the voltage can be higher or lower depending on load and
the current is probably only a maximum continuous rating.

I disassembled a couple of non-genuine car chargers and examined
the circuitry. They both used a Switch-Mode regulator chip set to 6.0 V
and had strict current limiting. One had the current limit set to
500 mA. When plugged into a 3210, it worked for a minute before
displaying "Not Charging". The other charger had a max. current of
550 mA and worked perfectly. When I adjusted the first charger to
550 mA it worked ok too. The same phone works perfectly on the
ACP-7A rated at 355 mA. Without a current limiter, the ACP-7A
allows you to draw > 355 mA (briefly) with only a slight
voltage drop. The regulated car adaptors cut the volts off
completely if you try to go over the current limit.


Conclusion:

The phone contains its own charging control circuit which will accept a
range of voltages - maybe 3 to 6 V. It needs to convert this
efficiently down to 2.4 or 3.6 V depending on the battery type.

The current drawn varies, as the battery is pulse-charged and the phone
repeatedly checkes its voltage. The phone will abort the charge process
if it can't get more than 500 mA. I think the phone tries to sense if
the adapter can deliver more than 550 mA. eg. if you are using the
optional "Fast, Light Travel Charger". If it can get 800 mA or more
without the voltage dropping, it will charge the phone faster. But it
doesn't mind if it only gets 550 mA.

"John" <jwnospam@nospamunico.com.au> wrote in message
news:hpjsf2-qmu.ln1@centauri.unico.com.au...
> Uncle Bully wrote:
>> "Bruce" <nomail@bigpond.net.au> wrote in message
>> news:ssWVd.183735$K7.133083@news-server.bigpond.net.au...
>>
>>>5.7V 800mA
>>>same as AC charger.
>>>"no name" <noemail> wrote in message news:42283230$1@dnews.tpgi.com.au...
>>>| You know the stock standard nokia car charger, the one that works on
>>>pretty
>>>| much all Nokia phone's, does anybody know the output on this? i assume
>>>it
>>>| pushes out 12V, how many amp?
>>>|
>>
>>
>>
>> Mine is 3.7V, 355mA
>
> Did you read that off the standard ACP-7A AC charger?

Oops, didn't read the 'car' charger bit. The above is for my GPO recharger.