Design Applications

ExpressCard™ Adapter – Forward Bridge

The PEX 8112 can be used to quickly upgrade legacy PCI

adapter board designs to be compatible with PCI Express

standard interface slots. In Figure 2, an existing CardBus™ IC

is converted for use on an ExpressCard™ with the addition of

the single-chip PEX 8112.

Figure 2. Forward Bridge in ExpressCard™

Embedded Host Platform – Reverse Bridge

The PEX 8112 supports Reverse bridging, enabling designers

to utilize the latest PCI Express silicon with widely entrenched

PCI host systems. Reverse bridging allows the host processor

to reside on the PCI bus; the PEX 8112 will accept

configuration cycles from the PCI side and manage the PCI

Express interface as a secondary entity within the PCI

software model as in Figure 3.

Figure 3. Reverse Bridge with PCI CPU

Development Tools

PEX 8112 Reference Design Kits (RDK) enable rapid customer design. The Reverse Bridge RDK (Figure 4) includes a standard

PCI connector (card-edge) and a standard PCI Express slot on the secondary side. The Forward Bridge RDK (Figure 5) includes the

PEX 8112 with a single x1 PCI Express port (card-edge) and four PCI slots on the secondary side. Each PEX 8112RDK can be

installed in a motherboard to evaluate PEX 8112 features and validate customer software.

Figure 4. Reverse Bridge RDK

Figure 5. Forward Bridge RDK

.

PCI Bus

ExpressCard

™

PEX

8111

CardBus

Silicon

PCI Bus

ExpressCard

™

PEX

8112

CardBus

Silicon

Product Ordering Information

Part Number

Description

PEX8112-AA66BI F

PCI Express to PCI Bridge, Standard-Pitch BGA Package, Lead Free

PEX8112-AA66FBI F

PCI Express to PCI Bridge, Fine-Pitch BGA Package, Lead-Free

PEX8112RDK-F

Forward Bridge Reference Design Kit

PEX8112RDK-R

Reverse Bridge Reference Design Kit

© 2007 PLX Technology, Inc. All rights reserved. PLX and the PLX logo are registered trademarks of PLX Technology, Inc. ExpressLane is a trademark of PLX Technology, Inc., which may be

registered under some jurisdiction. All other product names that appear in this material are for identification purposes only and are acknowledged to be trademarks or registered trademarks of their

respective companies. Information supplied by PLX is believed to be accurate and reliable, but PLX Technology, Inc. assumes no responsibility for any errors that may appear in this material. PLX

Technology, Inc. reserves the right, without notice, to make changes in product design or specification.

PCI8112-SIL-PB-P1-1.0

PLX Technology, Inc.

870 Maude Ave.

Sunnyvale, CA 94085 USA

Tel: 1-408-774-9060

Fax: 1-408-774-2169

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Host

CPU

PCI Slots

PEX

8112

PCI

Express

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