ep2s130 Altera Corporation, ep2s130 Datasheet - Page 76

• Manufacturer Part Number: ep2s130
• Description: Stratix Ii Device Family Data Sheet
• Manufacturer: Altera Corporation

PLLs & Clock Networks
Figure 2–44. Stratix II Enhanced PLL
Notes to
(1)
(2)
(3)
(4)
2–68
Stratix II Device Handbook, Volume 1
Global or
Regional
Clock
INCLK[3..0]
Each clock source can come from any of the four clock pins that are physically located on the same side of the device
as the PLL.
If the feedback input is used, you lose one (or two, if FBIN is differential) external clock output pin.
Each enhanced PLL has three differential external clock outputs or six single-ended external clock outputs.
The global or regional clock input can be driven by an output from another PLL, a pin-driven dedicated global or
regional clock, or through a clock control block, provided the clock control block is fed by an output from another
PLL or a pin-driven dedicated global or regional clock. An internally generated global signal cannot drive the PLL.
(4)
Figure
4
Shaded Portions of the
PLL are Reconfigurable
2–44:
FBIN
Switchover
Circuitry
Clock
(2)
Enhanced PLLs
Stratix II devices contain up to four enhanced PLLs with advanced clock
management features.
/n
Phase Frequency
Detector
PFD
Note (1)
Charge
Pump
Lock Detect
& Filter
Spectrum
Spread
/m
Filter
Loop
VCO Phase Selection
Affecting All Outputs
VCO Phase Selection
Selectable at Each
PLL Output Port
Figure 2–44
VCO
8
shows a diagram of the enhanced PLL.
Post-Scale
Counters
/c0
/c1
/c2
/c3
/c4
/c5
From Adjacent PLL
6
Altera Corporation
4
8
6
Global
Clocks
Regional
Clocks
I/O Buffers (3)
to I/O or general
routing
May 2007