Axcelerator Family FPGAs
v2.8
1-1
General Description
Axcelerator offers high performance at densities of up to
two million equivalent system gates. Based upon the
Actel AX architecture, Axcelerator has several system-
level features such as embedded SRAM (with complete
FIFO control logic), PLLs, segmentable clocks, chip-wide
highway routing, and carry logic.
Device Architecture
Actel's AX architecture, derived from the highly-
successful SX-A sea-of-modules architecture, has been
designed for high performance and total logic module
entire floor of the Axcelerator device is covered with a
grid of logic modules, with virtually no chip area lost to
interconnect elements or routing.
Programmable Interconnect
Element
The Axcelerator family uses a patented metal-to-metal
antifuse programmable interconnect element that resides
page 1-2). This completely eliminates the channels of
routing and interconnect resources between logic
modules (as implemented on traditional FPGAs) and
enables the efficient sea-of-modules architecture. The
antifuses
are
normally
open
circuit
and,
when
programmed,
form
a
permanent,
passive,
low-
impedance connection, leading to the fastest signal
propagation in the industry. In addition, the extremely
small size of these interconnect elements gives the
Axcelerator family abundant routing resources.
The
very
nature
of
Actel's
nonvolatile
antifuse
technology provides excellent protection against design
pirating and cloning (FuseLock technology). Cloning is
impossible
(even
if
the
security
fuse
is
left
unprogrammed) as no bitstream or programming file is
ever downloaded or stored in the device. Reverse
engineering is virtually impossible due to the difficulty of
trying
to
distinguish
between
programmed
and
unprogrammed
antifuses
and
also
due
to
the
programming methodology of antifuse devices (see
Figure 1-1 Sea-of-Modules Comparison
Switch
Matrix
Routing
Logic Block
Logic
Modules
Sea-of-Modules
Architecture
Traditional FPGA
Architecture