摘要 |
A direct current input power supply voltage Vcc is outputted to the load side via a PNP type transistor having a small Vce. A base thereof is driven by a base current from which noise is removed in a power source noise removing circuit. An input to the noise removing circuit is produced by shifting a level from the Vcc side by a direct current level shift circuit. Since an output voltage Vs varies with reference to Vcc and a voltage drop is relatively small owing to the transistor, an operation voltage on the load side can be ensured. The noise removing circuit is constituted by a gm amplifier. In order to increase a noise removing rate at low frequencies, by setting gm of a time constant C/gm to a small value, it is possible to set a capacity to a value which allows integration.
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