| 摘要 |
PURPOSE: To surely distinguish a trigger signal from a noise and to exactly output a reset signal by holding the signal levels of an external terminal at different elapse of time, respectively from a time when a signal is inputted to the external terminal and detecting the that they are set at prescribed levels. CONSTITUTION: The counters 3a, 3b of a clock circuit in a reset circuit clock different prescribed time, respectively starting from a time when the signal is inputted to the external terminal 1. A holding circuit 5a holds the signal level of the terminal 1 at the time when the clock of the counter 3a for the prescribed time is completed, and also, a holding circuit 5b holds the signal level of the terminal 1 at the time when the clock of the counter 3b for the prescribed time is completed. A logic circuit 8 outputs a detection signal by detecting that both output signals of the circuits 5a, 5b are set at the prescribed levels, and outputs the reset signal. |
