Variable Precision DSP Blocks User Guide: Agilex™ 5 FPGAs and SoCs

ID 813968
Date 9/20/2024
Public
Document Table of Contents

1.2.1. Fixed-point Arithmetic

Table 1.  Supported Combinations of Operational Modes and Features
Variable-precision DSP Block Resource Operation Mode Supported Operation Instance Pre-adder Support Coefficient Support Input Cascade Support Chainin/Chainout Support
1 variable precision DSP block Fixed-point independent 18 x 19 multiplication 2 1 Yes Yes Yes 2 No
Fixed-point independent 27 x 27 multiplication 1 Yes Yes Yes 3 Yes
Fixed-point two 18 x 19 multiplier adder mode 1 Yes Yes Yes 2 Yes
Fixed-point 18 x 18 multiplier adder summed with 36-bit input 1 No No No Yes
Fixed-point 18 x 19 systolic mode 1 Yes Yes Yes2 Yes
Fixed-point six 9 x 9 multiplier adder mode 1 No No No Yes
INT16 complex multiplication 1 No No No No
2 Variable precision DSP blocks Fixed-point complex 18x19 multiplication 1 No No Yes No
Table 2.  Supported Combinations of Operational Modes and Dynamic Control Features
Variable-Precision DSP Block Resource Operation Mode Dynamic ACCUMULATE Dynamic LOADCONST Dynamic SUB Dynamic NEGATE Dynamic Scanin Dynamic Chainout
1 variable precision DSP block Fixed-point six 9 x 9 multiplier adder mode Yes Yes No No No Yes
Fixed-point independent 18 x 19 multiplication No No No No Yes No
Fixed-point independent 27 x 27 multiplication Yes Yes No Yes No Yes
Fixed-point two 18 x 19 multiplier adder mode Yes Yes Yes Yes Yes Yes
Fixed-point 18 x 18 multiplier adder summed with 36-bit input Yes Yes Yes Yes No Yes
Fixed-point 18 x 19 systolic mode Yes Yes Yes Yes Yes Yes
INT16 complex multiplication No No Yes No No No
2 variable precision DSP blocks Fixed-point complex 18 x 19 multiplication No No No No No No
1 The Quartus® Prime software will determine the merging of two independent multiplication automatically when there are not enough DSP blocks on the device or within a Logic Lock (Standard) region.
2 Each of the two inputs to a pre-adder has a maximum width of 18-bit. When the input cascade is used to feed one of the pre-adder inputs, the maximum width for the input cascade is 18-bit.
3 When you enable the pre-adder feature, the input cascade support is not available.