| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To absorb noise generated in a reference voltage source down to a low band, while suppressing deterioration of ripple rejection ratio. <P>SOLUTION: This constant voltage circuit comprises a transistor Q1 inputting a negative reference voltage generated in the reference voltage source 1 to a base, a resistor R2 connected to the emitter of the transistor Q1, a CR Filter circuit consisting of a resistor R1 cutting a high-pass component from the emitter output of the transistor Q1 and a capacitance C1, a transistor Q2 inputting the output voltage of the CR filter circuit and outputting it to the output terminal 2, and transistors Q3-Q5 controlling the voltage Vout of the output terminal 2, according to the emitter current of the transistor Q1. In the transistors Q4 and Q5, emitters and correctors thereof are reverse-connected, whereby the formation of parasitic capacitance at nodes ND1 and ND2 and the output terminal 2 is prevented. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
