EPM7064STC44-6 Altera, EPM7064STC44-6 Datasheet - Page 13

• Manufacturer Part Number: EPM7064STC44-6
• Description: MAX 7000/S/AE/B
• Manufacturer: Altera

Figure 6. Parallel Expanders
Altera Corporation
Unused product terms in a macrocell can be allocated to a neighboring macrocell.
36 Signals
from PIA
Expanders
16 Shared
The compiler can allocate up to three sets of up to five parallel expanders
automatically to the macrocells that require additional product terms.
Each set of five parallel expanders incurs a small, incremental timing
delay (t
Compiler uses the five dedicated product terms within the macrocell and
allocates two sets of parallel expanders; the first set includes five product
terms and the second set includes four product terms, increasing the total
delay by 2 × t
Two groups of 8 macrocells within each LAB (e.g., macrocells
1 through 8 and 9 through 16) form two chains to lend or borrow parallel
expanders. A macrocell borrows parallel expanders from lower-
numbered macrocells. For example, macrocell 8 can borrow parallel
expanders from macrocell 7, from macrocells 7 and 6, or from macrocells
7, 6, and 5. Within each group of 8, the lowest-numbered macrocell can
only lend parallel expanders and the highest-numbered macrocell can
only borrow them.
borrowed from a neighboring macrocell.
PEXP
). For example, if a macrocell requires 14 product terms, the
PEXP
Product-
Product-
Select
Select
Matrix
Matrix
Term
Term
.
MAX 7000 Programmable Logic Device Family Data Sheet
Figure 6
Macrocell
Previous
From
shows how parallel expanders can be
Macrocell
To Next
Preset
Clock
Clear
Preset
Clock
Clear
Macrocell
Product-
Term Logic
Macrocell
Product-
Term Logic
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