Thank you for your replies.

Sorry I forgot to mention, it is for an off the shelf data logger and i do not have acces to recode the device, it will only work with the 24lc512, i have tried changing it to a 24lc1025, but the device does not work. so what i need to do is build an external circuit on which to have multiple 24lc512 eeproms and power up one at a time once the previous becomes full, using the high output from a port on the 16f876 as the Vcc for the 24lc512.