Intel IXP46X manual 3.12.3Supporting 5 V PCI Interface, Compact PCI Bus, cPCI J1, Transparent PCI

Models: IXP45X IXP46X

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Figure 16. PCI Interface

Intel® IXP45X and Intel® IXP46X Product Line of Network Processors—General Hardware Design Considerations

Figure 16. PCI Interface

Intel® IXP46X

 

 

 

 

 

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Network Processor

 

 

 

 

 

 

 

 

 

Compact PCI Bus

cPCI J1

PCI Interface

PCI Bus

Transparent PCI

Bridge

 

 

J2

 

 

 

 

 

cPCI

 

PCI Slots

 

 

 

 

 

 

 

 

 

B4110- 001

3.12.3Supporting 5 V PCI Interface

It is possible to support 5 V PCI devices with the help of voltage logic translators. One option can be implemented with voltage level translator. The Texas Instruments* family of FET bus switches CBT devices can be a good solution. The 10-bit SN74CBT3384A has been proven to work very effectively with the Intel® IXP465 Network Processor. All control and DATA/ADDRESS signals (bidirectional and not) need to be translated before connecting the 3.3 V to the 5 V logic together. Signals which are not used, do not need to be translated, simply follow the recommendations described in Table 20.

Figure 17 shows a block diagram of the interface required to perform the conversion. Ensure that all signals connect to either of the two interfacing logic levels.

TPROP (Bus Propagation Delay) is the maximum time for a complete flight. When you calculate TPROP, you must include in your timing calculation the TPD (Time for Propagation Delay) of the voltage translator. For details, refer to Section 6.2.

Intel® IXP45X and Intel® IXP46X Product Line of Network Processors

 

HDD

February 2007

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Document Number: 305261; Revision: 004

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Intel IXP46X, IXP45X manual 3.12.3Supporting 5 V PCI Interface, Compact PCI Bus, cPCI J1, Transparent PCI, Bridge, PCI Slots