| 摘要 |
<p>A disclosed constant voltage power supply circuit (1) has an input terminal (Vdd), an output terminal (Vout), a constant voltage power supply unit (2) that generates a constant voltage (Vo1) with a ripple voltage (Vri), and a ripple removing circuit unit (3) for removing the ripple voltage so that a constant voltage (V1) without the ripple voltage is output at the output terminal (OUT). The ripple removing circuit unit comprises a resistor (R1) connected between the constant voltage power supply unit and the output terminal; a ripple voltage detection circuit unit (5) for detecting the ripple voltage and outputting a signal depending on the detected ripple voltage; and a current circuit unit (6, 7) for receiving the signal from the ripple voltage detection circuit unit and supplying a current (io1) to the output terminal or absorbing a current (io2) from the resistor in response to the received signal, so as to cancel the ripple voltage at the output terminal.</p> |
