CONSTANT VOLTAGE POWER SUPPLY CIRCUIT

PROBLEM TO BE SOLVED: To provide a constant voltage power supply circuit compatible with a plurality of specifications having different allowable ranges of a limited current value against overcurrent.SOLUTION: A constant voltage power supply circuit 30 is a semiconductor integrated circuit that has a Vcc terminal, a C- terminal, a C+ terminal, a CPO terminal, a REGIN terminal, and a REGO terminal as terminals; and includes a booster circuit part 32, a constant voltage circuit part 34, a drooping type overcurrent protection circuit part 36, and an output voltage dependent type overcurrent protection circuit part 38. Output current detection in the drooping type overcurrent protection circuit part 36 is performed by using an external resistor 20 which is connectedly arranged in series between the CPO terminal and the REGIN terminal; and the output current detection in the output voltage dependent type overcurrent protection circuit part 38 is performed by using an internal resistor 76.