5V power on 90Q?

[Lawrence C Leung]

To add to Marc's excellent response:

Induction coils in-line (series) will also help reduce voltage pulses.
The caps would have to be run in parallel. No idea on how to size either
in the case of a car, spikes and drops are too variable to predict. BTW,
if you make such a power supply, to fight quick spikes (non-cyclic)
you'll probably need to add thermistors like what is found in a surge
surpressor. This means that your rigged PS will have a useful life,
limited by the thermistors. Personnally, I'd buy a car cigarette lighter
charger for the laptop at the local office supply store and be done with
it. 

LL - NY

On Sun, 25 Feb 2001 21:41:37 -0500 "Marc Swanson"
<marcswanson at mediaone.net> writes:
>> Quick question,
>>
>> Does EVERYTHING run at 12V on the 89 90q...or would there be
>> something that
>> runs at either 5V, 7V, or 8.5V??
>>
>> I'd like to directly power a laptop inside my car...without the
>> need to buy a
>> power inverter.
>
>
>Off hand the only thing that comes to mind is the ISV which runs at 
>9v.. I'm
>sure there are other things as well but be carefull:  You need to make 
>sure
>that you have enough current to supply the laptop.  Not to mention 
>that
>sensitive electronics like laptops don't like large fluctuations in
>voltage/current which are quite common in most of the cars electrics.  
>If
>you really don't want to buy an inverter you could just build an 
>appropriate
>voltage divider to bring the voltage down a bit from 12v plus a 
>capacitor or
>two to handle swings in power supply (and sizing the 
>resistors/capacitors
>right can be tricky as load changes as things are turned on/off).  By 
>the
>time you've gone through all of this work you've just built yourself 
>the
>equivalent of an off the shelf regulated power supply minus the 
>conversion
>from 120v AC :-)
>
>
>-Marc-
>
>
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