| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an overcurrent detecting circuit which is capable of detecting, without power loss or malfunctions, even for respect to the output current supplied from a low-output amplifier to a load. <P>SOLUTION: A current detecting resistor R1 is connected in series between an output amplifier 12 and a load output terminal 13. One end of the current detecting resistor R1 is connected to the emitter of an overcurrent detecting transistor Q1. The other end is connected with +Vcc via a resistance-type potential divider, comprising a series circuit of resistors R2 and R6. The divided voltage of the resistance type potential divider is inputted to the base of the transistor Q1. The sum of the divided voltage and the voltage drop, in the current detecting resistor R1, is taken as the base-emitter voltage of the overcurrent detecting transistor Q1. A protective transistor Q2 is controlled by the output of the overcurrent detecting transistor Q1. <P>COPYRIGHT: (C)2004,JPO |
