MULTI-INPUT SIGNATURE REGISTER

摘要

PURPOSE:To reduce a structural area of a register by making a feedback to an initial-stage exclusive OR gate from a last-stage delay element among a plurality of delay elements composing a linear feedback shift register to input a test train with the number of items thereof being odd. CONSTITUTION:Flip flops Di (i=1-n-1) are provided as delay elements the same in the number as signal lines of a test data. A feedback is made to a head exclusive OR gate 2 through a feedback loop 5 from a last-stage flip flop Dn-1. A test train with the number of items thereof being odd is inputted into a signature register thus arranged to allow the suppressing of error overlooking probability to about 1/2. Thus, the structure of the signature regis ter can be minimized without lowering a capacity simply by adjusting the num ber of items of a test train to be inputted to an odd value.