Embedded Memory in Stratix Series FPGAs

The Stratix^® family of FPGAs introduced the concept of TriMatrix memory. In TriMatrix memory, the on-chip memory is implemented in three types of different block sizes, each for a specific use. The memory type has been maintained and optimized through devices in the Stratix series.

With significant architectural changes to the internal memory in Stratix V FPGAs, we've significantly increased both the capacity and bandwidth of these structures. Stratix V FPGAs utilize two types of memory: enhanced memory logic array blocks (MLABs) and M20K memory blocks. These changes have enhanced performance and utilization, improving capabilities for digital signal processing (DSP) designs. Quartus^® II software automatically migrates designs from previous Stratix series FPGA memory architectures to the new structure.
Key enhanced MLAB features improve efficiency and bandwidth:

• Address and data registers internal to MLAB
  • Increased performance
  • Reduced logic use
• Increased efficiency for wide, shallow FIFOs (n bits wide, 32 or 64 deep)

Key M20K memory block features enhance performance and utilization:

• Increased embedded memory bit counts
• Increased memory block performance
• Improved flexibility of memory architecture to span applications
• Simplified floorplanning and routability
• Optional hard error correction code (ECC) protection, which can operate in pipelined or non-pipelined modes

Quartus II software selects the best-fit memory for each instantiation to provide the most efficient embedded memory implementation.

Table 1 summarizes the differences in the memory blocks and related applications between recent Stratix FPGA families.

For full details on memory block capacity for Stratix V devices, see the Stratix V overview page.

For details on the memory block counts for earlier Stratix FPGA families, see the relevant handbook chapters.

Table 2 summarizes the features for each of the two internal memory types implemented in Stratix V FPGAs.