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View Full Version : Supercaps on a DS1302... What are these?



Chicago Mike
01-26-2006, 01:15 AM
I hear all about SuperCaps.... Especially with the DS1302 instead of long-life batteries.... I've found very little info on these. What qualifies as a supercap (spec wise) compared to a regular cap, and can anyone give me examples (say at DigiKey) that I can look at the specs on.... (That would work for the DS1302).

Thanks!ˇ

Paul Baker
01-26-2006, 01:27 AM
SuperCaps are very large value capacitors which have very low leakage current (seepage of electrons across the insulating dielectric in the capacitor), Electrolytic capacitors, while capable of large capacitances fail in the second respect and therefore are not suitible for battery backup operations. There are a few types capable of being SuperCaps, but the most readily availible are called AreoGel, seaching digikey with the term will show 20 such capacitors ranging from 0.1F to 50F availible in 2.5 and 5.0V ratings. The spec sheet for them lists other types: supercaps, ultracaps and EDLCs.

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ˇ1+1=10

Post Edited (Paul Baker) : 1/25/2006 5:30:16 PM GMT

Bruce Bates
01-26-2006, 02:34 AM
Mike -

Here is a typical "SuperCap":
http://www.allelectronics.com/cgi-bin/category/140910/Super.html

Regards,

Bruce Bates