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Switching Between Flash Eproms

Switching Between Flash Eproms

Switching Between Flash Eproms

(OP)
I need some help on a hobby project I'm doing. I'm trying to figure out the best way to switch between 2 or 3 flash eproms (AM29F400BB). Each one will hold a different set of data tables. The simplest way I can think of is to tie all the address pins/data pins together, and use the Ouput Enable pin of each device to select which eprom will supply the data to the Micro. When ouput is disable the pins are high impedance, I don't think that this will cause a problem but I'm not 100% sure. Can some one please tell me if I'm going in the right direction, and if not what is the right direction.
 Thanks in Advance
  Kurt.

RE: Switching Between Flash Eproms

That is a fine solution! You may want to not enable the chips either to save energy. (Some chips have an enable AND an output enable.) I don't know what your power situation is.

RE: Switching Between Flash Eproms

Why not use the CS (Chip Select) pin?  Each device has a CS pin.  This should simplify the connections, since all the devices will share the same signals (addr, data, OE, WE, etc), EXCEPT for the CS line.

RE: Switching Between Flash Eproms

(OP)
Thanks guys,
 I'm going to tie all the CS lines to the original CS line, so things act as they did before. I thought that OE was a better option to switch because the time for OE to Data Ouput is only 30ns, and from CS to Data Ouput is 70ns. I don't know if it would really make a difference, but you never know.

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