With the variable-precision digital signal processing (DSP) block, the Stratix® V FPGA supports, on a block-by-block basis, various precisions ranging from 9-bit x 9-bit up to single-precision floating point (mantissa multiplication) within a single DSP block. This frees you from FPGA architecture restrictions, allowing you to use the optimum precision at each stage of the DSP datapath. You'll also benefit from increased system performance, reduced power consumption, and reduced architectural constraints. Figure 1 shows the Stratix V FPGA variable-precision DSP block architecture in the 18-bit precision mode. Figure 2 shows the Stratix V FPGA variable-precision DSP block architecture in the high-precision mode.
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Webcast: Enabling High-Performance DSP with Stratix V Variable-Precision DSP Block Learn how our 28-nm Stratix V FPGA family, the industry’s first variable-precision DSP architecture, allows you to set the precision of each DSP block to suit your application. Find out how it can be set to accommodate the required precision growth within the DSP datapath. Suhel Dhanani, Sr. Manager, DSP Marketing |
White Paper: Enabling High-Performance DSP Applications with Stratix V Variable-Precision DSP Block (PDF)
Figure 1. Stratix V FPGA Variable-Precision DSP Block Architecture, 18-Bit Precision Mode
Figure 2. Stratix V FPGA Variable-Precision DSP Block Architecture, High-Precision Mode
Stratix V FPGA DSP Precision Range
| Table 1: Stratix V FPGA DSP Blocks in Single-Block Mode | |
| Single Variable-Precision DSP Block | Stratix V FPGA DSP Blocks |
| Three independent multipliers | 9x9 |
| Two multipliers in sum mode | 18x18 |
| Two multipliers in sum mode | 16x16 |
| Independent asymmetric | 18x36 |
| Independent high precision | 27x27 |
| Table 2: Stratix V FPGA DSP Blocks in Multiple-Block Mode | |
| Multiple Variable-Precision DSP Blocks in Cascade Mode | Stratix V FPGA DSP Blocks |
| One independent 36x36 | 2 |
| One independent 54x54 | 4 (1) |
| 18x18 complex multiply | 2 |
| 18x25 complex multiply | 3 |
| 18x36 complex multiply | 4 |
| 27x27 complex multiply | 4 |
- Requires additional logic outside the DSP block
Cascade Bus
All modes feature a 64-bit accumulator and each variable-precision DSP block comes with a 64-bit cascade bus that allows the implementation of even higher precision signal processing by cascading multiple blocks using a dedicated bus.
The variable-precision DSP architecture maintains backward compatibility. It can efficiently support existing 18-bit DSP applications, such as high-definition video processing, digital up or down conversion, and multi-rate filtering.
Applications for Stratix V FPGAs
- Video processing applications
- Wireless applications
- Medical applications
- Test and measurement applications
- Military radar applications
Related Links
- Stratix V FPGAs
- Altera® DSP solutions
- DSP intellectual property (IP) cores
- DSP Builder
- Variable Precision DSP Blocks in Stratix V Devices (PDF)
