A control circuit includes a plurality of drive current output circuits, a control
voltage generating circuit, a first current output circuit, a second current output
circuit, a voltage divider and a compensation voltage generating circuit. The voltage
divider has one end connected to the control voltage generating circuit and a plurality
of nodes each of which connected to the respective drive current output. The drive
current output circuit outputs the control voltage to the drive circuits based
on a power supply voltage and the control voltage. The compensation voltage generating
circuit outputs a compensated voltage based on the difference between the current
outputted from the first current output circuit and the current outputted from
the second current output circuit. In order to supply the compensation voltage
to the other end of the voltage divider, the values of the respective control voltage
are equalized.
