| 摘要 |
PURPOSE:To obtain a stable constant voltage even with a very low voltage power source by generating an output voltage with a current flowing through a PNP transistor (TR). CONSTITUTION:A starting circuit 21 when powered on flows a current I11 to turn on a TRQ8. Then, TRs Q2 and Q3, and Q4 and Q5 operate with a current Ix to flow current I5 and I3, turning on the PNP TRQ7. Consequently, an output voltage Vs is developed at the 3rd terminal and a current Iy is supplied from the power source to a resistance R3 through the PNP TRQ3. The output voltage Vs is fed back by this PNP TRQ7 and stabilized with the output current Iy. The lower-limit voltage of operation is determined by th sum voltage of the output voltage Vs and the saturation voltage of the PNP TRQ7. |
