| 摘要 |
PURPOSE: A differential current output device is provided to change an output current smoothly according to the variation of a differential input voltage as decreasing chip area. CONSTITUTION: A differential input circuit(10) includes the first constant current source outputting a constant current, and the first and the second differential amplification transistor dividing the first constant current by amplifying an input voltage differentially, and the first current mirror source transistor generating the first mirror source voltage proportional to the first current, and the second current mirror source transistor generating the second mirror source voltage proportional to the second current. A current subtraction circuit(20) includes the first mirror pre transistor flowing the first mirror current by receiving the first mirror source voltage, and the second mirror pre transistor flowing the second mirror current by receiving the second mirror source voltage, and outputs a current according to a difference current between the first mirror current and the second mirror current. A branch circuit(30) branches the supply destination of a current output indication signal according to the intensity of the difference current, according to the polarity of the difference current. And a current output circuit(40) has a plurality of output transistor circuits including the third mirror source transistor and the third mirror pre transistor, and supplies a forward or reverse output current to a load according to the polarity and the intensity of the difference current.
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