OVERCURRENT DETECTION CIRCUIT

摘要

PROBLEM TO BE SOLVED: To obtain an overcurrent detection circuit in which an accelerative temperature rise at an object to be protected can be prevented accurately in an overcurrent state at a high temperature. SOLUTION: A comparator circuit 1 in which a reference voltage V0 is compared with a comparison voltage V0' derived according to an output current and in which a current exceeding an overcurrent limit value is detected so as to judge an overcurrent is provided. An output-stage circuit 2 which stops the output current when the overcurrent is detected by the comparator circuit 1 is provided. A constant-current circuit 3 by which a bias current is supplied to the comparator circuit 1, in which a change in the comparison voltage V0' in the comparator circuit 1 is regulated, thereby reduces the overcurrent limit value I0C to be set by the reference voltage V0 and the comparison voltage V0' with increase in the temperature is installed.