| 摘要 |
PURPOSE:To attain the tests of an input buffer and an external wiring as well as an LSI internal circuit just with addition of a small number of circuits. CONSTITUTION:The flip-flops 11-14 are provided to a pseudo random number pattern generator together with the selectors 21-24, and an exclusive OR gate 30. Then the pattern generator performs three types of actions according to the values of the 1st and 2nd action mode signals c1 and c2. That is, the function of a conventional pseudo random number pattern generator is secured with c1=c2='1', the function of a boundary scan buffer is secured with c1='1' and c2='0', and the function of an input buffer is secured with c1='0' respectively. |
