
1–62
Altera Corporation
Stratix II Device Handbook, Volume 2
July 2009
PLL Specifications
PLL
Specifications
f
Stratix II GX Device Handbook (or the Stratix II Device Handbook) for
information about PLL timing specifications
Clocking
Stratix II and Stratix II GX devices provide a hierarchical clock structure
and multiple PLLs with advanced features. The large number of clocking
resources in combination with the clock synthesis precision provided by
enhanced and fast PLLs provides a complete clock-management solution.
Global and Hierarchical Clocking
Stratix II and Stratix II GX devices provide 16 dedicated global clock
networks and 32 regional clock networks. These clocks are organized into
a hierarchical clock structure that allows for 24 unique clock sources per
device quadrant with low skew and delay. This hierarchical clocking
scheme provides up to 48 unique clock domains within the entire
Stratix II or Stratix II GX device.
Table 1–17 lists the clock resources
available on Stratix II devices.
There are 16 dedicated clock pins (CLK[15..0]) on Stratix II and
Stratix II GX devices to drive either the global or regional clock networks.
Four clock pins drive each side of the Stratix II device, as shown in
and 1–40. Enhanced and fast PLL outputs can also drive the
global and regional clock networks.
Table 1–17. Clock Resource Availability in Stratix II and Stratix II GX Devices (Part 1 of 2)
Description
Stratix II Device Availability
Stratix II GX Device Availability
Number of clock input pins
24
12
Number of global clock networks 16
16
Number of regional clock
networks
32
Global clock input sources
Clock input pins, PLL outputs, logic
array
Clock input pins, PLL outputs, logic
array, inter-transceiver clocks
Regional clock input sources
Clock input pins, PLL outputs, logic
array
Clock input pins, PLL outputs, logic
array, inter-transceiver clocks
Number of unique clock sources
in a quadrant
24 (16 global clocks and 8 regional
clocks)
24 (16 GCLK and 8 RCLK clocks)
Number of unique clock sources
in the entire device
48 (16 global clocks and 32 regional
clocks)
48 (16 GCLK and 32 RCLK clocks)