| 摘要 |
PROBLEM TO BE SOLVED: To reduce the loss of an emitter resistor without increasing the number of elements. SOLUTION: A chopper type switching power source is provided with a control transistor Q2, in which a collector is connected to a base of a switching transistor Q1, an emitter resistor R4 connected between the emitter of the control transistor Q2 and the ground level, a Zener diode D6 connected between the output terminal of an inductor L5 and the emitter of the control transistor Q2, and a voltage-dividing circuit 21 which divides the voltage at the output terminal of the inductor L5 and gives the divided output to the base of the control transistor Q2. |
