ep1s25 Altera Corporation, ep1s25 Datasheet - Page 89

• Manufacturer Part Number: ep1s25
• Description: Stratix Device Family Data Sheet
• Manufacturer: Altera Corporation

Altera Corporation
July 2005
Figure 2–42. Global Clocking
Note to
(1)
Regional Clock Network
There are four regional clock networks within each quadrant of the Stratix
device that are driven by the same dedicated CLK[15..0] input pins or
from PLL outputs. From a top view of the silicon, RCLK[0..3] are in the
top left quadrant, RCLK[8..11] are in the top-right quadrant,
RCLK[4..7] are in the bottom-left quadrant, and RCLK[12..15] are in
the bottom-right quadrant. The regional clock networks only pertain to
the quadrant they drive into. The regional clock networks provide the
lowest clock delay and skew for logic contained within a single quadrant.
RCLK cannot be driven by internal logic. The CLK clock pins
symmetrically drive the RCLK networks within a particular quadrant, as
shown in
from PLLs and CLK pins.
CLK[3..0]
The corner fast PLLs can also be driven through the global or regional clock
networks. The global or regional clock input to the fast PLL can be driven by an
output from another PLL, a pin-driven global or regional clock, or internally-
generated global signals.
Figure
Figure
2–42:
Global Clock [15..0]
2–43. See
CLK[7..4]
Figures 2–50
Note (1)
CLK[15..12]
Stratix Device Handbook, Volume 1
Global Clock [15..0]
and
2–51
for RCLK connections
Stratix Architecture
CLK[11..8]
2–75