| 摘要 |
PURPOSE: To provide two current detection differential amplifiers together with a testing circuit for testing entire rows along one word line and to simultaneously test entire rows of memory array without adding a sense amplifier. CONSTITUTION: When every cell correctly stores logic 1, current does not flow to a teat line TL, and the current which is equal to a product acquired from current derived by a single memory cell and the number of accessed memory cells flows to a complementary test line TLB. When current does not exist in the line TL, an output of a 1st differential amplifier 10 becomes low, and when current exists in the line TLB, an output of a 2nd differential amplifier 12 becomes high. A comparator 14 detects two opposite logic states of logical value of the test amplifiers 10 and 12 and outputs value of the logic 1 which shows that appropriate data is stored in memory cell. This means that the test result for entire memory cells along the word line is satisfactory. |
