LOW-VOLTAGE DETECTION CIRCUIT

摘要

PROBLEM TO BE SOLVED: To detect a low-voltage state precisely with a simple configuration. SOLUTION: A low-voltage detection circuit comprises: a first transistor element 31 operating according to an input voltage; a second transistor 33 for prescribing an auxiliary supply voltage that is higher than an internal supply voltage by operation following the operation of the first transistor; a third transistor 38 for prescribing a low-voltage detection voltage between the auxiliary supply voltage and the internal supply voltage by operation following the operation of the first transistor; a first resistor 32 for prescribing the operating point of the second transistor; and a second resistor 40 for prescribing the operating point of the third transistor. When the auxiliary supply voltage becomes the low-voltage detection voltage or smaller, the third transistor detects a decrease in the auxiliary supply voltage. COPYRIGHT: (C)2008,JPO&INPIT