Constant current circuit operating independent of temperature

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.