摘要 |
A current mirror circuit that provides an excellent current that does not deteriorate, even when the power source is lower supply voltage. A mirror current flows in a first MOS transistor when a constant current flows in the MOS transistor from a current source. A subtracter outputs the difference between voltage Vg1 of the gate of the MOS transistor and voltage Vd1 of the drain, and applies this difference to the gate of a second MOS transistor. When the power-supply voltage of this circuit becomes lower supply voltage and the absolute value of Vd1 decreases, the MOS transistors enter the triode region, and the mirror current decreases. when the absolute value of Vd1 decreases, because the difference between Vg1 and Vd1 becomes larger, the drain current of the second MOS transistor increases, and the amount by which the mirror current decreases is counterbalanced.
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