RPIXP2800BB Intel, RPIXP2800BB Datasheet - Page 85

• Manufacturer Part Number: RPIXP2800BB
• Manufacturer: Intel

Specifications of RPIXP2800BB

• Operating Supply Voltage (typ): 1.3/1.5/2.5/3.3V
• Operating Supply Voltage (max): 1.575/2.7/3.465V
• Operating Supply Voltage (min): 1.235/2.3/3.135V
• Mounting: Surface Mount
• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Lead Free Status / Rohs Status: Not Compliant

Figure 48.
4.8.2
Hardware Design Guide
Figure 48
Four-QDR SRAM Load Routing Recommendations
Determining Loopclock Length for QDRII SRAM Used by
IXDP2800 Advanced Development Platform
This section describes how to determine functional platforms with the best possible timing margin
by using two- and four-load examples. Although SRAM devices are used in the examples, the
principles and calculations described apply to any load on the channel, including TCAM.
Figure 49
no termination resistors are required. By removing termination resistors, power is conserved, BOM
count is reduced, and board layout is simplified. Using one clock pair (C_H[0], C_L[0], K_H[0],
K_L[0]) from the IXP28XX network processor to drive the SRAM devices and the other pair
(C_H[1], C_L[1]) to clock the Q data back into the IXP28XX network processor, provides the
widest timing margin. Each clock is effectively point-to-point, reducing the load of each clock and
decreasing uncertainty.
* Note: Loopback clock length is determined from paper analysis.
Network Processor
shows the optimal interconnections for the two QDR load conditions. It is optimal in that
illustrates routing recommendations for a four-QDR SRAM load.
Intel
Actual implemented length may vary and should be
determined by performing a detailed timing analysis using
extracted layout parasitics.
®
Data, Controller,
IXP2800
SRAM Clks
CIN[0]
C[1]
Loopback Clock Trace: 9.75"
3.0"
1.0"
1.0"
*
0.11"
IXP28XX Network Processor
0.11"
1.0"
0.02"
0.02"
1.0"
100 Ohms
100 Ohms
SRAM1
SRAM2
SRAM3
SRAM4
QDR
QDR
QDR
QDR
QDR SRAM
B3419-01
0.75V
0.75V
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