Power-efficient sign extension for booth multiplication methods and systems

A power-efficient sign extension circuit associated with a digital signal process for performing a Booth multiplication process, comprising:

• sign-application circuitry for applying a sign bit in a Booth multiplication tree comprising a plurality of partial product rows, each of said partial product rows comprising a partial product for a Booth multiplication process, said sign bit for use in the event of the Booth multiplication process requiring a sign extension step;
• multiplication circuitry for one-extending a predetermined partial product row of said Booth multiplication tree using a sign bit for preserving the correct sign of said predetermined partial product row;
• sign value resolution circuitry for resolving the signal value of said sign bit by generating a sign-extension bit in said Booth multiplication tree, said sign-extension bit positioned in a carry-out column to extend the product of the Booth multiplication process;
• and
• said multiplication circuitry further for forming a final product from said Booth multiplication tree by adding said carry-out value to said sign bit to at least a predetermined column of said Booth multiplication tree for effectively extending the sum component of said final product with the sign and zero-extending the carry component of said final product.

A digital signal processor for operation in support of a personal electronics device, said digital signal process comprising means for performing a power-efficient sign extension for a Booth multiplication process, said comprising the steps of:

• means for applying a sign bit in a Booth multiplication tree comprising a plurality of partial product rows, each of said partial product rows comprising a partial product for a Booth multiplication process, said sign bit for use in the event of the Booth multiplication process requiring a sign extension step;
• means for one-extending a predetermined partial product row of said Booth multiplication tree using a sign bit for preserving the correct sign of said predetermined partial product row;
• means for resolving the signal value of said sign bit by generating a sign-extension bit in said Booth multiplication tree, said sign-extension bit positioned in a carry-out column to extend the product of the Booth multiplication process;
• and
• means for forming a final product from said Booth multiplication tree by adding said carry-out value to said sign bit to at least a predetermined column of said Booth multiplication tree for effectively extending the sum component of said final product with the sign and zero-extending the carry component of said final product.

A computer usable medium having computer readable program code means embodied therein for performing a power-efficient sign extension method for a Booth multiplication process, comprising:

• computer readable program code means for applying a sign bit in a Booth multiplication tree comprising a plurality of partial product rows, each of said partial product rows comprising a partial product for a Booth multiplication process, said sign bit for use in the event of the Booth multiplication process requiring a sign extension step;
• computer readable program code means for one-extending a predetermined partial product row of said Booth multiplication tree using a sign bit for preserving the correct sign of said predetermined partial product row;
• computer readable program code means for resolving the signal value of said sign bit by generating a sign-extension bit in said Booth multiplication tree, said sign-extension bit positioned in a carry-out column to extend the product of the Booth multiplication process;
• and
• computer readable program code means for forming a final product from said Booth multiplication tree by adding said carry-out value to said sign bit to at least a predetermined column of said Booth multiplication tree for effectively extending the sum component of said final product with the sign and zero-extending the carry component of said final product.