STPCI0180BTC3 STMICROELECTRONICS [STMicroelectronics], STPCI0180BTC3 Datasheet - Page 51

• Manufacturer Part Number: STPCI0180BTC3
• Description: PC Compatible Embedded Microprocessor
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

6.2 HIGH SPEED SIGNALS
Some Interfaces of the STPC run at high speed
and have to be carefully routed or even shielded.
Here is the list of these interfaces, in decreasing
speed order:
- Memory Interface.
- Graphics and video interfaces
- PCI bus
- 14MHz oscillator stage
Figure 6-8. Shielding signals
ground pad
Issue 1.1
All the clocks have to be routed first and shielded
for speeds of 27MHz or more. The high speed sig-
nals have the same contrainsts as some of the
memory interface control signals.
The next interfaces to be routed are Memory, Vid-
eo/graphics, and PCI.
All the analog noise sensitive signals have to be
routed in a separate area and hence can be rout-
ed indepedently.
ground pad
ground ring
shielded signal line
shielded signal lines
BOARD LAYOUT
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