Hello All,

  I've got a PCF8583 RTC, and can't get it stable.  The problem is that it
has to be build in a device.  Normally it would run off the (stabilized) 5
Volt supply, but when the device is turned off, it has to run on a
(non-stabilized) source.

My first attempt was to pull it to 5 Volts, and let it drop to about 2.4
volts (NiCad).  But this made the clock deviate horribly.

The second attempt was to let the clock run on a 3.6 volts NiCad that get's
trickle-charged.  But even the difference between a fully charged NiCad
(4.2 Volts) and a somewhat empty one ( < 3.3 Volts ) was enough to throw
the RTC off ....

So, Can anyone help me to get a stable, NiCad back-upped, RTC ?

Regards,
  Rudy Wieser

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