ep1s25 Altera Corporation, ep1s25 Datasheet - Page 151

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

Figure 2–73. High-Speed Differential I/O Receiver / Transmitter Interface Example
Altera Corporation
July 2005
105 MHz
840 Mbps
R4, R8, and R24
Interconnect
Dedicated
Interface
Receiver
+
–
Fast
PLL
8×
■
■
Dedicated Circuitry
Stratix devices support source-synchronous interfacing with LVDS,
LVPECL, 3.3-V PCML, or HyperTransport signaling at up to 840 Mbps.
Stratix devices can transmit or receive serial channels along with a
low-speed or high-speed clock. The receiving device PLL multiplies the
clock by a integer factor W (W = 1 through 32). For example, a
HyperTransport application where the data rate is 800 Mbps and the
clock rate is 400 MHz would require that W be set to 2. The SERDES factor
J determines the parallel data width to deserialize from receivers or to
serialize for transmitters. The SERDES factor J can be set to 4, 7, 8, or 10
and does not have to equal the PLL clock-multiplication W value. For a J
factor of 1, the Stratix device bypasses the SERDES block. For a J factor of
2, the Stratix device bypasses the SERDES block, and the DDR input and
output registers are used in the IOE. See
An external pin or global or regional clock can drive the fast PLLs, which
can output up to three clocks: two multiplied high-speed differential I/O
clocks to drive the SERDES block and/or external pin, and a low-speed
clock to drive the logic array.
RapidIO
HyperTransport
rx_load_en
Data
8
Interconnect
tx_load_en
Local
8
Data
8
8×
Stratix Device Handbook, Volume 1
Figure
2–73.
Stratix Architecture
Dedicated
Transmitter
Interface
+
–
Regional or
global clock
840 Mbps
2–137