摘要 |
A power-on/off reset circuit comprises a capacitor, a first transistor, a second transistor, a first current mirror circuit, a second current mirror circuit, and an inverter. In a power-on mode where the source voltage gradually increases in level, the capacitor is charged via the first transistor. The first current mirror circuit comprising a pair of transistors allows a current to flow therein in proportion to a potential of the capacitor. The second transistor converts the current to a voltage, which is input to the inverter to provide a first reset signal in the power-on mode. In a power-off mode where the source voltage gradually decreases in level, the second current mirror circuit comprising a pair of transistors temporarily increases the input voltage of the inverter to provide a second reset signal.
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