NEGATIVE OUTPUT DIRECT CURRENT STABILIZING POWER-SUPPLY UNIT AND BOTH POSITIVE AND NEGATIVE OUTPUT DIRECT CURRENT STABILIZING POWER SUPPLY-UNIT USING THE SAME

摘要

PROBLEM TO BE SOLVED: To make satisfactory suitability with a power supply control circuit of a microcomputer, etc., by allowing a 2nd transistor to make an emitter side a higher level than a base side that is connected to a ground line, outputting collector current to the base of a 1st transistor and making on/off driving of the 1st transistor. ;SOLUTION: The base of a 1st transistor Tr11 is connected to the collector of a 2nd transistor Tr12, and the base of the transistor Tr12 is connected to a high side terminal P12 through a resistor R12 and also gives an on/off control signal Vc which is inputted to a control input terminal P11 of an emitter through a resistor R11. And, the signal Vc is made a higher level than that of the high side input terminal P12, collector current of the transistor Tr12 is outputted to the base of the transistor Tr11 to turn on the transistor Tr11 and the terminal P12 is made conductive to a terminal P13.;COPYRIGHT: (C)1999,JPO