AV-51001
2013.05.06
17
Variable-Precision DSP Block
Table 14: Variable-Precision DSP Block Configurations for Arria V Devices
Usage Example
Multiplier Size (Bit)
DSP Block Resource
Low precision fixed point for video
applications
Three 9 x 9
1
Medium precision fixed point in FIR
filters
Two 18 x 18
1
FIR filters
Two 18 x 18 with accumulate
One 27 x 27
1
1
Single-precision floating-point
implementations
Very high precision fixed point
implementations
One 36 x 36
2
You can configure each DSP block during compilation as independent three 9 x 9, two 18 x 18, or one 27 x 27
multipliers. Using two DSP block resources, you can also configure a 36 x 36 multiplier for high-precision
applications. With a dedicated 64 bit cascade bus, you can cascade multiple variable-precision DSP blocks
to implement even higher precision DSP functions efficiently.
Table 15: Number of Multipliers in Arria V Devices
The table lists the variable-precision DSP resources by bit precision for each Arria V device.
Independent Input and Output Multiplications Operator
18 x 18 Mul-
18 x 18 Mul- tiplier Adder
tiplier Adder Summed
Mem-
ber
Code
Variable-
precision
DSP Block
9 x 9 Multi- 18 x 18 Mul- 27 x 27 Mul- 36 x 36 Mul-
Variant
plier
tiplier
tiplier
tiplier
Mode
with 36 bit
Input
A1
A3
A5
A7
B1
B3
B5
B7
C3
C7
D3
D7
240
396
720
480
240
396
—
—
—
—
—
—
—
—
—
—
—
—
240
396
240
396
1,188
1,800
2,400
2,760
3,135
3,276
3,468
1,188
2,400
3,135
3,468
792
600
1,200
1,600
1,840
2,090
2,184
2,312
792
600
600
600
800
800
800
800
Arria V
GX
920
920
920
920
1,045
1,092
1,156
396
1,045
1,092
1,156
396
1,045
1,092
1,156
396
1,045
1,092
1,156
396
800
1,600
2,090
2,312
800
800
800
Arria V
GT
1,045
1,156
1,045
1,156
1,045
1,156
1,045
1,156
Arria V Device Overview
Altera Corporation
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