I'm trying to design a circuit with Ramtron's non-volatile parallel FRAM with built-in RTC - the FM3808.
The datasheet states that the FRAM works differently than SRAM, in that it needs the chip enable CE/ to toggle between each access and not stay low. This is because it is needed for the necessary precharge period.
I'm using an Atmel ATmega128's external memory bus, and will be having other devices on the bus as well. I've seen a schematic with the ALE connected to the CE/ and the address / data bus connected together since the FRAM has an internal latch - but this would leave the FRAM on the bus all the time, and I have other devices mapped.
Is there a simple way to put this chip on a memory bus without conflicting with other devices, and generating the necessary toggling of the CS/ line?
Does anyone have any experience with this chip, or it's smaller brother the FM1808? Any sample schematics to steer me right?
And is the FRAM too slow to be used with no-wait states on an ATmega128 running at 16mhz?
Thanks