Hi Joe,

I guess I'm confused with this thread. I'm probably missing something
obvious. It sounds like the RTC is only drawing 7 uA when the main Vcc is
switched off and you are ok with that.

Here's where I'm confused:

Why does it matter to you if the pull-ups become "a burden" if you have a
dead PIC? Your schematic shows a NiCad battery -- the battery will just get
discharged. I could see if the battery was a non-rechargeable type, as this
could get expensive (replacing batteries), but you have a rechargeable
battery that can just get recharged, right? The board will be useless anyway
with the dead PIC and the 470 ohm resistor will limit current output on the
NiCad. Most SuperCaps have a pretty high internal resistance so it probably
will discharge gracefully as well.

Please understand that I'm not trying to be you on the spot or anything --
I'm just trying to better understand this thread so that I could offer any
help to you (if I'm able to). I've worked with the Philips PCF8563 RTC in
the past. In my case, I did not have the liberty to use large-value pull-ups
since serial EEPROMs were also connected to the I2C bus.

Best regards Joe,

Ken Pergola

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