ORT82G5 Datasheet, PDF (9/92 Pages) Agere Systems – ORCA ORT82G5 1.0.1-25/2.0-2.5/3.125 Gbits/s Backplane Interface FPSC

Preliminary Data Sheet
July 2001
ORCA ORT82G5 FPSC Eight-Channel
1.0-1.25/2.0-2.5/3.125 Gbits/s Backplane Interface
Description (continued)
The SLIC is connected from PLC routing resources
and from the outputs of the PFU. It contains eight
3-state, bidirectional buffers, and logic to perform up to
a 10-bit AND function for decoding, or an AND-OR with
optional INVERT to perform PAL-like functions. The
3-state drivers in the SLIC and their direct connections
from the PFU outputs make fast, true, 3-state buses
possible within the FPGA, reducing required routing
and allowing for real-world system performance.
Programmable I/O
The Series 4 PIO addresses the demand for the flexi-
bility to select I/Os that meet system interface require-
ments. I/Os can be programmed in the same manner
as in previous ORCA devices, with the additional new
features which allow the user the flexibility to select
new I/O types that support high-speed interfaces.
Each PIO contains four programmable I/O pads and is
interfaced through a common interface block to the
FPGA array. The PIO is split into two pairs of I/O pads
with each pair having independent clock enables, local
set/reset, and global set/reset. On the input side, each
PIO contains a programmable latch/flip-flop which
enables very fast latching of data from any pad. The
combination provides for very low setup requirements
and zero hold times for signals coming on-chip. It may
also be used to demultiplex an input signal, such as a
multiplexed address/data signal, and register the sig-
nals without explicitly building a demultiplexer with a
PFU.
On the output side of each PIO, an output from the PLC
array can be routed to each output flip-flop, and logic
can be associated with each I/O pad. The output logic
associated with each pad allows for multiplexing of out-
put signals and other functions of two output signals.
The output FF, in combination with output signal multi-
plexing, is particularly useful for registering address
signals to be multiplexed with data, allowing a full clock
cycle for the data to propagate to the output. The out-
put buffer signal can be inverted, and the 3-state con-
trol can be made active-high, active-low, or always
enabled. In addition, this 3-state signal can be regis-
tered or nonregistered.
The Series 4 I/O logic has been enhanced to include
modes for speed uplink and downlink capabilities.
These modes are supported through shift register
logic, which divides down incoming data rates or multi-
plies up outgoing data rates. This new logic block also
supports high-speed DDR mode requirements where
data is clocked into and out of the I/O buffers on both
edges of the clock.
The new programmable I/O cell allows designers to
select I/Os which meet many new communication stan-
dards permitting the device to hook up directly without
any external interface translation. They support tradi-
tional FPGA standards as well as high-speed, single-
ended, and differential-pair signaling (as shown in
Table 1). Based on a programmable, bank-oriented I/O
ring architecture, designs can be implemented using
3.3 V, 2.5 V, 1.8 V, and 1.5 V referenced output levels.
Routing
The abundant routing resources of the Series 4 archi-
tecture are organized to route signals individually or as
buses with related control signals. Both local and global
signals utilize high-speed buffered and nonbuffered
routes. One PLC segmented (x1), six PLC segmented
(x6), and bused half chip (xHL) routes are patterned
together to provide high connectivity with fast software
routing times and high-speed system performance.
Eight fully distributed primary clocks are routed on a
low-skew, high-speed distribution network and may be
sourced from dedicated I/O pads, PLLs, or the PLC
logic. Secondary and edge-clock routing is available for
fast regional clock or control signal routing for both
internal regions and on device edges. Secondary clock
routing can be sourced from any I/O pin, PLLs, or the
PLC logic.
The improved routing resources offer great flexibility in
moving signals to and from the logic core. This flexibil-
ity translates into an improved capability to route
designs at the required speeds when the I/O signals
have been locked to specific pins.
Agere Systems Inc.
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