Patent ID: 7948480

Claim:
A current driving apparatus comprising: a plurality of current driving circuits, each of the plurality of current driving circuits including: a reference current input terminal to which a first reference current is given; a current mirror circuit for receiving, at an input end thereof, the first reference current given to the reference current input terminal and outputting, from an output end thereof, a first internal current corresponding to the first reference current; a bias voltage generation section for receiving the first internal current from the current mirror circuit and generating a bias voltage corresponding to the first internal current; an output reference current generation section for receiving the bias voltage generated by the bias voltage generation section and generating a second reference current corresponding to the bias voltage; a reference current output terminal for outputting the second reference current generated by the output reference current generation section to the outside; an internal current generation transistor for receiving at a gate thereof the bias voltage generated by the bias voltage generation section and generating a second internal current corresponding to the bias voltage; and an output current generation section for receiving the second internal current generated by the internal current generation transistor and generating n output currents corresponding to the second internal current, wherein: the reference current input terminal of an Mth one of the plurality of current driving circuits is connected to the references current output terminal of an (M−1)th one of the plurality of current driving circuits, where M is an integer equal to or greater than 2, in the bias voltage generation section, a current/voltage conversion coefficient for conversion from the first internal current to the bias voltage is changeable by a first control signal, and in the output reference current generation section, a voltage/current conversion coefficient for conversion from the bias voltage to the second reference current is changeable by a second control signal.