| 摘要 |
<p>PURPOSE:To obtain a stable and noiseless semiconductor integrated circuit by generating a pulse edge signal from a Schmitt trigger circuit, delaying the generated signal with a monostable multivibrator circuit, and after stabilizing a power supply voltage, generating a power ON signal. CONSTITUTION:When the power supply voltage Vcc is inputted, a pulse edge signal is generated from the Schmitt trigger circuit 15 on the way of the rise of the power supply. A POR signal attended with the application of a power source is raised after a time delay corresponding to the time constant of a CR from the pulse edge signal. The raised POR signal is fed back from a node E to a NOR gate 18 and the output of the gate 18 is fallen. Since the output of the gate 18 is transmitted to an inverter 20 through a CR delay circuit, the pulse of the POR signal is fallen with a time delay based upon the CR time constant. Since the POR signal is outputted after completely raising the power supply voltage VCC, a stable and noiseless POR signal can be generated.</p> |
