Hi All,
PCB design Guru's or experts please help me know what are Tips or guidlines for 4 layered PCB designing.
I am basically developing Spartan 3 board. Using OrCad 9.0
Since you have a ground player now (I'm assuming), carefully watch signal return paths of critical signals. Following a signal from it's source to the destination, and then follow the path on the GND plane right under the signal's trace. This path should be unobstructed in order to improve signal integrity.