Intel 31154 manual About This Document, Terminology and Definitions

	About This Document
About This Document	1

This document provides layout information and guidelines for designing platform or add-in board applications with the Intel® 31154 133 MHz PCI Bridge.

This document is intended to be used as a guideline only. Intel recommends that you employ best- known design practices with board-level simulation, signal-integrity testing, and validation for a robust design. Please note that this design guide focuses on specific design considerations for the 31154 Bridge and is not intended to be an all-inclusive list of all good design practices. Use this guide as a starting point, and use empirical data to optimize your particular design.

1.1Terminology and Definitions

Table 1.	Terminology and Definition (Sheet 1 of 2)
	Term				Definition
	31154	Intel® 31154 133 MHz PCI Bridge
						Stripline in a PCB is composed of the
						conductor inserted in a dielectric with GND
						planes to the top and bottom, as shown in the
	Stripline					cross-section diagram at left.
						NOTE: An easy way to distinguish stripline
						from microstrip is that you need to
						strip away layers of the board to view
						the trace on stripline.
						Microstrip in a PCB is composed of the
	Microstrip					conductor on the top layer above the
						dielectric with a ground plane below, as
						shown in the cross-section diagram at left.
		Prepreg is material used for the lamination process of manufacturing PCBs. It consists of a
	Prepreg	layer of epoxy material that is placed between two cores. This layer melts into epoxy when
		heated and forms around adjacent traces.
	Core	Core material is used for the lamination process of manufacturing PCBs. This material is two-
		sided laminate with copper on each side. The core is an internal layer that is etched.
				Layer 1: copper		Printed circuit board: An example PCB
						manufacturing process consists of the
				Prepreg		following steps:
				Layer 2: GND		• A PCB consists of alternating layers of
				Core		core and prepreg stacked.
						• The finished PCB is heated and cured.
	PCB			Layer 3: VCC
						• The via holes are drilled.
				Prepreg
				Layer 4: copper		• Plating covers holes and outer surfaces.
						• Etching removes unwanted copper.
		Example of a cross-section of				• The PCB is tinned, coated with solder
			a four-layer stack
						mask, and silk-screened.

Intel® 31154 133 MHz PCI Bridge Design Guide Design Guide 7