Another possibility would be a rechargeable coin cell. I haven't dealt with them in quite a while, but from what I recall you could get a 3.3 V Li-ion cell about the size of a fat quarter that you could trickle charge. As long as you are adding more energy than you are using this scheme will work. Good luck and let us know what your final solution is. Eric Martens > -----Original Message----- > From: [EMAIL PROTECTED] [SMTP:[EMAIL PROTECTED]] > Sent: Thursday, May 11, 2000 10:41 AM > To: Palm Developer Forum > Subject: Re: Powering a device from the Palm III - knew I missed > something > > I don't altogether dislike the idea of using a big cap as a PS (as least > it's better than a battery, which would have to be installed in a way that > > it's user-replaceable). > > But wouldn't 1 F be a problem? i.e. w/ 330 Ohm on the VCC pin on the palm, > > you get RC = 330 sec then x 5= a heck of a long time for the cap to charge > > up! Mind you the cap would then be pretty much a big battery when charged. > > Using 1000 uF as per Jose's rough math means tau = 0.33 sec which might be > > allright...hmm. > > Maybe it's time I sat at the bench and began the endless process of > fiddling... > > Kris > > At 08:45 PM 5/10/00, you wrote: > >On 11-May-2000 Jose Rodriguez wrote: > > > > > 1000 uF is quite big (bad news), even for a low voltage (10V?) > capacitor. > > > But you get the idea of the tradeoff between voltage drop and > capacitor > > > value. > > > >Just use one of those 5.5V memory capacitors -- like the one in the Palm. > At > >1 Farad they are still fairly small. The one in the Palm is .1 Farad. > > > > > >/* Chris Faherty <[EMAIL PROTECTED]> */ > >/* Your Stock has crashed - you must now restart your system */ > > > > > >-- > >For information on using the Palm Developer Forums, or to unsubscribe, > >please see http://www.palmos.com/dev/tech/support/forums/ > > > -- > For information on using the Palm Developer Forums, or to unsubscribe, > please see http://www.palmos.com/dev/tech/support/forums/ -- For information on using the Palm Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/tech/support/forums/
