| 摘要 |
PURPOSE:To prevent the malfunction of switching the set mode of a signal processing circuit because of noise infiltrated to a reset input terminal in the semiconductor integrated circuit which uses the reset input terminal and a terminal for test mode setting in common. CONSTITUTION:The malfunction is prevented by detecting the noise using a Schmitt trigger circuit 2 for removing the noise by using its voltage level for discrimination and a noise removing circuit 7 provided with a delay element 12 for removing the noise by using its pulse width for discrimination. On the other hand, a signal pulse able to be detected/removed by the noise removing circuit 7 is inputted to an up counter 4 and when its counting overflows, a test circuit 6 outputs a test mode setting signal SIT. |
