| 摘要 |
According to an embodiment of the present invention, a constant current source circuit comprises: to a voltage supply unit to which a control voltage is supplied; a first comparator to compare the control voltage inputted into a non-inverting terminal (+) and a first input voltage inputted into an inverting terminal (-); a transistor to control a gate end to equalize the control voltage inputted into the inverting terminal (-) of the first comparator and the first input voltage inputted into the non-inverting terminal; a second comparator comprising an inverting terminal to receive a second input voltage outputted from the transistor, and a non-inverting terminal to receive a third input voltage, and equalizing the second input voltage and the third input voltage to control a second output current; a first resistor connected between the inverting terminal of the second comparator and an output terminal of the second comparator; and a second resistor connected between the non-inverting terminal of the second comparator and the output terminal of the second comparator. A resistance ratio of the first resistor and the second resistor can be controlled to generate the second output current which flows through the second resistor and is lower than a first output current flowing through the first resistor. |
