Hello,

I'm looking for some guidance on a 12Mhz SPI link design. I have an arm processor pushing data into a SPI flash chip at 12Mhz. I would like to put my flash memory chips on a separate board that plugs into the main board where my arm is so that I can basically have a plugin card with multiple memory chips and having them on their own (small) PCB will free up real estate on my main board. I've read a lot about reflection issues and signal integrity problems and am not sure if this is a good idea at 12Mhz due to these issues. My trace lengths would still be short, < 5in but would be going through via/board to board header.

My question basically is whether it is possible/good idea to have a small plug in card with some flash chips on it which will be connected to the ARM via standard 100mil board headers at this speed. I know sharp corners and vias are avoided, but if I can pull this off reliably with adding some series resistors for reflections etc...it would be worth it.

Anyways, any input on this topic would be greatly appreciated as I'm going into hardware design and this is a pretty big driver in my design.

Thanks a lot,
Rob

 

12 mhz- card-to-card sounds like trouble if single ended signaling is employed.
I would use some differential line drivers / receivers to move the signals around.