| 摘要 |
PURPOSE:To make it possible to measure the threshold voltage of an input buffer circuit irrespective of the movement of the inner circuits by a method wherein a circuit, with which the limit of the H-level threshold voltage and the L-level threshold voltage of the input buffer circuit will be determined, is provided. CONSTITUTION:The title semiconductor integrated circuit consists of the inner circuit 4 containing the input buffer, consisting of inverters 1-3, a logic circuit and the like, the test circuit 12 containing an inverter 5 which works as an output buffer, a NAND circuit 6, an NOR circuit 7, an EX-NOR circuit 8 and transfer gates 9 and 10. When the threshold voltage of an input buffer circuit is measured and determined, an operation mode signal 106 is set at an L-level. Accordingly, an H-level is inputted into the transfer gate 9 through an inverter 11, and the L-level is inputted into the transfer gate 10. As a result, the threshold value of the input buffer circuit can be measured.
|
