| 摘要 |
<p>The malfunction of an output voltage caused by external noise is prevented without an increase in the capacitance of a capacitor of a delay circuit. The delay circuit comprises a constant current source, connected to the capacitor via a first node, for charging or discharging the capacitor, a charge/discharge circuit for discharging or charging the capacitor when an input voltage changes to a first level and charging or discharging the capacitor when the input voltage changes to a second level, and a voltage detecting circuit for changing the level of the output voltage from the first level to the second level after a delay of a time from when the charge/discharge of the capacitor is started till when the voltage of the first node exceeds a predetermined detection voltage. In the delay circuit, the malfunction of the output voltage is prevented by providing a voltage holding circuit for holding the voltage of the first node at a level exceeding the detection voltage when the input voltage is at the second level and the output voltage changes to the second level.</p> |
