Patent ID: 6886127

Claim:
A circuit for computing the function log(e x 1 +e x 2 ) or ln(e x 1 +e x 2 ) for a first argument value x 1 and a second argument value x 2 , said circuit comprising: a table storing a first data field including a plurality of table index values and a second data field including a plurality of computed table values corresponding to said plurality of table index values; wherein said plurality of table index values are selected from a predefined range of |x 1 −x 2 | argument values and scaled by a first scaling factor; and said plurality of computed table values are computed based on the equation log(1+e −|x 1 −x 2 | ) or ln (1+e −x 1 −x 2 | ) for each of said |x 1 −x 2 | argument values selected for said table index values, and scaled by said first scaling factor.