2–22
Altera Corporation
Stratix II GX Device Handbook, Volume 2
October 2007
Transmitter Modules
Figure 2–10. Clock Distribution for a Four-Lane Configuration
Note to
Figure 2–10
:
(1)
The Global Clock line must be driven by an input pin.
Eight-Lane Mode
The eight-lane mode (refer to
Figure 2–11
) is reserved for PIPE ×8 use
only. The central block of the lower transceiver supplies the parallel and
serial clocks for all eight transmitter channels. The clock distribution uses
a dedicated eight-lane clocking routing that offers low skew for
transmitter channel-to-channel skew specification. The high- and
low-speed clocks are forwarded using this dedicated eight-lane clocking
tree. The central block of the upper transceiver block and all the
transmitter clock generation blocks are unused and are powered down in
this mode. The clock to the PLD (
coreclkout
) is generated by the
central clock generation block of the master transceiver block (the lower
transceiver block).
Transmitter Channel 2
Transmitter Channel 0
Transmitter PLL Block
Transmitter PLL0
Transmitter Channel 3
Transmitter Channel 1
Transmitter PLL1
Central
Clock Divider
Block
coreclk_out
To PLD
Reference
clocks (refclks,
Global Clock
(1)
,
IQ Lines)
Central Block
÷
2