Currently I am designing a 4-layer PCB, with the layers as follows:
- (1st layer, top) signal
- (2nd layer) ground
- (3rd layer) power
- (4th layer, bottom) signal
The clock frequency is either 8 MHz (running at 3.3V) or 16 MHz (running at 5V). There are no active RF components on the board, just surface-mounted SPI-based devices. The total board dimensions are ~4cm x ~3cm.
My current design has no copper pour on the signal layers, but have copper pour on the ground and power layers.
So under these circumstances, would it make any difference whether or not I have a copper pour on the top and bottom signal layers?