ep1agx50d Altera Corporation, ep1agx50d Datasheet - Page 83

• Manufacturer Part Number: ep1agx50d
• Description: Arria Gx Device Data Sheet
• Manufacturer: Altera Corporation

Altera Corporation
May 2008
Multiplier
Multiply-accumulator
Two-multipliers adder
Four-multipliers adder
Table 2–14. Multiplier Size and Configurations per DSP Block
DSP Block Mode
Modes of Operation
The adder, subtractor, and accumulate functions of a DSP block have four
modes of operation:
■
■
■
■
Table 2–14
DSP block mode according to size. These modes allow the DSP blocks to
implement numerous applications for DSP including FFTs, complex FIR,
FIR, 2D FIR filters, equalizers, IIR, correlators, matrix multiplication, and
many other functions. DSP blocks also support mixed modes and mixed
multiplier sizes in the same block. For example, half of one DSP block can
implement one 18 × 18-bit multiplier in multiply-accumulator mode,
while the other half of the DSP block implements four 9 × 9-bit multipliers
in simple multiplier mode.
DSP Block Interface
The Arria GX device DSP block input registers can generate a shift
register that can cascade down in the same DSP block column. Dedicated
connections between DSP blocks provide fast connections between shift
register inputs to cascade shift register chains. You can cascade registers
within multiple DSP blocks for 9 × 9- or 18 × 18-bit FIR filters larger than
four taps, with additional adder stages implemented in ALMs. If the DSP
block is configured as 36 × 36 bits, the adder, subtractor, or accumulator
stages are implemented in ALMs. Each DSP block can route the shift
register chain out of the block to cascade multiple columns of DSP blocks.
Four two-multiplier adder
Two four-multiplier adder
Eight multipliers with
eight product outputs
(two 9 × 9 complex
multiply)
Simple multiplier
Multiply-accumulator
Two-multipliers adder
Four-multipliers adder
9 × 9
shows the different number of multipliers possible in each
—
Four multipliers with four
product outputs
Two 52-bit multiply-
accumulate blocks
Two two-multiplier adder
(one 18 × 18 complex
multiply)
One four-multiplier adder
18 × 18
Arria GX Device Handbook, Volume 1
One multiplier with one
product output
Arria GX Architecture
36 × 36
—
—
—
2–75