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Product Specification

LogiCORE IP Block Memory Generator v6.1

multiplexers than the minimum area algorithm. Figure 24 shows two examples of memories built

using the low power algorithm.

Note:

In Spartan-6 devices, two 9K block RAMs are used for one 1Kx18.

Fixed Primitive Algorithm

The fixed primitive algorithm allows the user to select a single block RAM primitive type. The core will

build the memory by concatenating this single primitive type in width and depth. It is useful in

systems that require a fixed primitive type. Figure 25 depicts two 3kx16 memories, one built using the

2kx9 primitive type, the other built using the 4kx4 primitive type.

Note that both implementations use four block RAMs, and that some of the resources utilized extend

beyond the usable memory space. It is up to the user to decide which primitive type is best for their

application.

The fixed primitive algorithm provides a choice of 16kx1, 8kx2, 4kx4, 2kx9, 1kx18, 512x36, 256x72 and

256x36 primitives. The primitive type selected is used to guide the construction of the total user

memory space. Whenever possible, optimizations are made automatically that use deeper embedded

X-Ref Target - Figure 24

Figure 24: Examples of the Low Power Algorithm

X-Ref Target - Figure 25

Figure 25: Examples of the Fixed Primitive Algorithm

3kx16 Memory

1kx18

5kx17 Memory

1kx18

3kx16 memory

2kx9

3kx16 memory

4kx4 4kx4 4kx4 4kx4

1 2 ... 18 19 20 21 22 23 24 25 26 27 28 ... 117 118

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