Re: [NTLK] Car Adapter for Newtons

From: Johannes Wolf (mp2100_at_mail-gw.estec.esa.int)
Date: Fri Feb 11 2005 - 00:04:25 PST


The point is that the Newt will not draw infinite current,
but simply relies on the current limiting function of the power supply.
Thus if you connect a power supply that can deliver more than 1.2 Amps at
6V,
the Newt will take all it can get depending on the charging status of the
battery.
The charging current is mainly dependent on the voltage difference between
battery and power supply, so you may reach 2 Amps and more which is simply
too much for the Newt - the built in fuse will blow and certainly a few
other parts as well.

Keep in mind that this is true only in case there is a rechargeable battery
inside the Newt.
Otherwise the Newt will draw a quiet predictable more or less constant and
LOW current (below 150-200mA) and can easily accept a voltage range between
6V and 7.5V

Cheers
Johannes

> -----Original Message-----
> From: newtontalk-bounce_at_newtontalk.net
> [mailto:newtontalk-bounce_at_newtontalk.net]On Behalf Of Ed Kummel
> Sent: Wednesday, February 09, 2005 8:32 PM
> To: newtontalk_at_newtontalk.net
> Subject: Re: [NTLK] Car Adapter for Newtons

> I would be very leery in sticking any old power plug
> in your newt....There have been horror stories here
> about people taking all precautions in powering their
> newt with a non-Apple powersupply. The reason being is
> that the Newt has some weird power requirements that
> normal adaptors cannot supply (I remember something
> like the adaptor limits the maximum current draw
> because the Newt can request infinite current from the
> source?...correct me if I'm wrong...)
> And with parts becoming scarcer by the day and the
> number of people repairing these things live at the
> far reaches of the world, the last thing you would
> want is to have your Newt die because you plugged in a
> power adaptor that wasn't healthy for your Newt...
> If you need to use power in a car (GPS and GPRS PC
> card usage comes to mind as to why you would need
> this) then i suggest that you get a power inverter and
> use your Apple certified wall plug in your car.
> You can get these things cheap...
> http://www.softwareandstuff.com/h_tol_150wtpwrinv.html
> $25...its really a no-brainer!
> Ed

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