Patent ID: 6954058

Claim:
A constant current supply device comprising: a first current mirror circuit including a first transistor, a second transistor and a current detection resistor provided between an emitter of the first transistor and a current output terminal; a main transistor provided on a main current path starting from the current output terminal, passing through the current detection resistor and ending at a first power supply line; a first constant current circuit connected between a collector of the first transistor and the first power supply line as a constant current circuit for generating a constant current on the basis of a voltage appearing between a base and emitter of a transistor; a second constant current circuit; and a second current mirror circuit including a third transistor connected between a collector of the second transistor and the first power supply line, a fourth transistor connected between the second constant current circuit and the first power supply line, and a first compensation resistor connected between an emitter of the third transistor and the first power supply line and having a positive temperature coefficient, wherein a collector of the fourth transistor is connected to a base of the main transistor.