CYNSE70256-66BHC Cypress Semiconductor Corp, CYNSE70256-66BHC Datasheet - Page 66

• Manufacturer Part Number: CYNSE70256-66BHC
• Manufacturer: Cypress Semiconductor Corp

Specifications of CYNSE70256-66BHC

• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Package Type: BGA
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Not Compliant

The Search command is a pipelined operation and executes a Search at one-fourth the rate of the frequency of CLK2X for 288-
bit searches in ×288-configured tables. The latency of SADR, CE_L, ALE_L, WE_L, SSV, and SSF from the 288-bit Search
command (measured in CLK cycles) from the CLK2X cycle that contains the C and D cycles is shown in Table 10-23.
Table 10-23. Search Latency from Instruction to SRAM Access Cycle
Search latency from command to SRAM access cycle is 5 for only a single device in the table and TLSZ = 01. In addition, SSV
and SSF shift further to the right for different values of HLAT, as specified in Table 10-24.
Table 10-24. Shift of SSF and SSV from SADR
10.6.6
The hardware diagram of the Search subsystem of fifteen devices is shown in Figure 10-48. Each of the four blocks in the diagram
represents a block of four CYNSE70256 devices except the last, which has three devices.The diagram for a block of four devices
is shown in Figure 10-49. The following are the parameters programmed into the fifteen devices.
Note:
Document #: 38-02035 Rev. *E
23. The matching address is always going to be location 0 in a four-entry page for 288-bit Search (two LSBs of the matching index will be 00).
24. All fifteen devices must be programmed with the same value for TLSZ and HLAT. Only the last bank in the last device in the table must be programmed with
• First thirty devices (devices 0–13, banks 0 and 1): CFG = 1010101010101010, TLSZ = 10, HLAT = 000, LRAM = 0, and
• Thirty-first device (device 30, Bank 0): CFG = 1010101010101010, TLSZ = 10, HLAT = 000, LRAM = 0, and LDEV = 0.
• Thirty-first device (device 30, Bank 1): CFG = 1010101010101010, TLSZ = 10, HLAT = 000, LRAM = 1, and LDEV = 1.
LDEV = 0.
Number of Devices
LRAM = 1 and LDEV = 1 (device number 14 in this case).
1–15 (TLSZ = 10)
1–4 (TLSZ = 01)
288-bit Search on Tables Configured as ×288 Using up to Fifteen CYNSE70256 Devices
HLAT
000
001
010
011
100
101
110
111
524,284
Location
address
GMR
12
L
0
4
8
K
287
287
A
0
Max Table Size
128K × 288 bits
480K × 288 bits
Figure 10-47. ×288 Table with Four Devices
CFG = 1010101010101010
(288-bit configuration)
B
1
C
2
Number of CLK Cycles
D
3
0
1
2
3
4
5
6
7
0
0
Latency in CLK Dycles
Must be same in each of banks
of each of the four devices
(First matching entry)
5
6
CYNSE70256
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