Patent ID: 7411442

Claim:
A constant current circuit formed as a semiconductor integrated circuit having a resistance element with negative temperature characteristics, and having a current mirror circuit including a first transistor in a first path and a second transistor in a second path, gates of the first transistor and the second transistor being connected to each other, and generating a first current for a first path depending on a second current flowing through the second path, the constant current circuit generating a constant current, the constant current circuit, comprising: a temperature compensation circuit, provided in parallel with the first path, for generating a third current having negative temperature characteristics, wherein the first path comprises a serial connection circuit including a first diode structure and a first resistance element connected between the first transistor and a predetermined reference power supply, the second path comprises a second diode structure connected between the second transistor and the reference power supply, the temperature compensation circuit comprises a third transistor and a second resistance element connected between the third transistor and the reference power supply, the second resistance element receives a voltage according to a voltage applied to the second diode structure, the third transistor configures the current mirror circuit with the first and second transistors and generates the third current depending on the second current, and the output current is formed by adding the first current and the third current.