Quantification - 2.6 English

Semi-Ternary CAM Search v2.6 LogiCORE IP Product Guide (PG319)

Document ID
PG319
Release Date
2023-11-01
Version
2.6 English

The total width of an entry is calculated as:

Entry Width = KEY_WIDTH + RESPONSE_WIDTH + PRIORITY_WIDTH + 1
The valid bit adds one extra bit to the entry width. In order to access the whole entry in parallel a number of block RAMs or URAMs are used. Block RAMs are allocated in data width increments of 64 bits. URAMs are allocated in data width increments of 128 bits (except for entry widths of 64 bits and less). To avoid quantification losses it is beneficial if the entry size is close below or on a data width boundary. For example, if the total block RAM entry size is 308 bits, the quantification loss is only 12 bits per entry: 5*64 - 308 = 12.

The maximum supported entry width is 2048 bits.