Signed multiplier circuit utilizing a uniform array of logic blocks

Abstract

A signed multiplier circuit includes a two-dimensional array of substantially similar logic blocks. Each of the logic blocks is programmable to implement any of four multiply functions of first and second inputs, in which: the first and second inputs are both signed; the first and second inputs are both unsigned; the first input is signed and the second input is unsigned; and the first input is unsigned and the second input is signed. Each logic block includes rows and columns of sub-circuits, e.g., logical AND gates and full adders. One row and one column of each logic block include a programmably invertible AND gate, with the row and column being independently controlled. The ability to program the logic block to perform all four of these functions enables the combination of rows and columns of the logic blocks to build large signed multipliers of virtually any size.