| 摘要 |
PURPOSE:To check simply each IC memory without removing the packaged IC memories by providing an IC memory having the same standard as an IC memory to be chaecked to actuate both memories in parallel to each other with the same address and same data and comparing the outputs of both memories to each other. CONSTITUTION:An IC memory 3 having the same standard as an IC memory 1 to be checked is connected to an IC socket 4. At the same time, the memory 1 is clipped by an IC clip 2 and the output of this memory 1 is supplied to a comparison memory display circuit 5 via switches SW3 and SW1 respectively. While the same address input data, control signal, etc. as the memory 1 are transmitted to the memory 3 via a switch SW2. The output signals of both memories are separated from each other since the contact of the SW2 corresponding these output signals is turned off. Then these separated signals are supplied separately to the circuit 5. Therefore the output of the memory 1 has no change as long as the memory 1 is normal. If the memory 1 has a fault, a difference is produced between both outputs since an error occurs when an access is given to the faulty area after an address change. |
