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Hello there,
I need to interface with an external NOR Flash chip via QSPI (XIP mode). My MCU will not run at higher frequency than 80 Mhz, so QSPI frequency is exactly that.
I have managed to connect all traces the way it can be seen in the attachment. In my opinion, the positive aspects of such routing are:
1. No VIa's,
2. The clock line is not close to any data line.
3. The clock line is straight, no serpents on it.
The cons I see are:
1. Lengths mismatch,
2. Clock line is the shortest.
I was wondering either for 80 Mhz I should incorporate length matching. I have preliminarly checked the possibilities, and I figured out that I could connect the chip with quite even traces, apart from #CS line, which would also need a via. What do you think? I would appreciate all help.
PS: I have uploaded also a second routing option with lengths matched, but clock signal is not straight anymore...
I need to interface with an external NOR Flash chip via QSPI (XIP mode). My MCU will not run at higher frequency than 80 Mhz, so QSPI frequency is exactly that.
I have managed to connect all traces the way it can be seen in the attachment. In my opinion, the positive aspects of such routing are:
1. No VIa's,
2. The clock line is not close to any data line.
3. The clock line is straight, no serpents on it.
The cons I see are:
1. Lengths mismatch,
2. Clock line is the shortest.
I was wondering either for 80 Mhz I should incorporate length matching. I have preliminarly checked the possibilities, and I figured out that I could connect the chip with quite even traces, apart from #CS line, which would also need a via. What do you think? I would appreciate all help.
PS: I have uploaded also a second routing option with lengths matched, but clock signal is not straight anymore...
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