At 22.16 2005.05.12 +0200, you wrote:
>I'd say the typical thing would be to "independize" the supply with a
>diode and add the supercap. That way you maintain power while
>preventing the supercap from discharging through other parts of the
>circuit:
>
>      |\ |
>+5V---| )|----+-------------------+
>      |/ |    |                   |VCC
>              |+              +-------+
>            ----- SUPERCAP    |  RTC  |
>            -----             +-------+
>              |                   |GND
>GND-----------+-------------------+
>
>Something like that should work. I think.

Depending on the supercap's ESR, I would add a serie resistor to it.
Inrush current can be very high for a very long time otherwise. :D


 
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