EP910 ALTERA [Altera Corporation], EP910 Datasheet - Page 5

• Manufacturer Part Number: EP910
• Description: The Altera Classic device family offers a solution to high-speed, lowpower logic integration. Fabricated on advanced CMOS technology
• Manufacturer: ALTERA [Altera Corporation]

Altera Corporation
Figure 3. Classic Feedback Multiplexer Configurations
Global Feedback Multiplexer
Global
EP610
EP610I
EP910
EP910I
Q
I/O
Mode 0
In Mode 0, the register
is clocked by the global
clock signal. The
output is enabled by
the logic from the
product term.
Mode 1
In Mode 1, the output
is permanently enabled
and the register is
clocked by the product
term, which allows
gated clocks to be
generated.
Figure 2. Classic Output Enable/Clock Select
Feedback Select
Each macrocell in a Classic device provides feedback selection that is
controlled by the feedback multiplexer. This feedback selection allows the
designer to feed either the macrocell output or the I/O pin input
associated with the macrocell back into the AND array. The macrocell
output can be either the Q output of the programmable register or the
combinatorial output of the macrocell. Different devices have different
feedback multiplexer configurations. See
Quadrant Feedback Multiplexer
Quadrant
OE = Product Term
CLK = Global
OE = Enabled
CLK = Product Term
EP1810
Array
Array
AND
AND
Q
I/O
Global
Global
Clock
Clock
Figure
Classic EPLD Family Data Sheet
VCC
VCC
Dual Feedback Multiplexer
Quadrant
Data
Data
Global
3.
CLK
CLK
OE
OE
CLR
CLR
Output Enable/Clock
Select
EP1810
Q
Q
Output Enable/Clock
Select
Macrocell
Output Buffer
Macrocell
Output Buffer
Q
I/O
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