DC-DC CONVERTER AND ELECTRONIC APPARATUS WITH THIS BUILT- IN DC-DC CONVERTER

摘要

PROBLEM TO BE SOLVED: To make it possible to supply power stably to a second load by supplying power from a rectifier and filter means connected to a current-limiting means to a first load that is less affected by voltage fluctuation and by supplying power from a rectifier and filter means not connected to a current-limiting means to the second load that is largely affected by the voltage fluctuation.;SOLUTION: A rectifier and filter means 14 comprises a series connected unit 7 made up of a rectifier diode 9 and a capacitor 11, and another series-connected unit 15 made up of a rectifier diode 8, a current-limiting means (a resistor 16) and a capacitor 10. A light source 12 that is less affected by voltage fluctuation is connected to the series-connected unit 15, and a measuring system 13 that is largely affected by the voltage fluctuation to the series-connected unit 7. Here, the electric potential at Point A becomes equal to the terminal voltage of the capacitor 10 plus the portions of the voltage drop caused by the rectifier diode 8 and resister 16. For the terminal voltage drop of the capacitor 11 caused by the power consumption of the measuring system 13, the capacitor 11 is charged at the time when its terminal voltage becomes equal to or lower than the terminal voltage minus the portion of the voltage drop caused by the rectifier diode 9.;COPYRIGHT: (C)2000,JPO