PURPOSE: To obtain a current drive circuit with simplified constitution by inserting a series circuit comprising a load and a resistor between an output of a voltage amplifier circuit and an output of an inverting circuit and feeding back a voltage at a voltage of a connecting point between the load and the resistor to the voltage amplifier circuit.

CONSTITUTION: A voltage is fed to an inverting input terminal of an operational amplifier 23 being a component of the voltage amplifier circuit is impressed from an input terminal 8 via a resistor R1 and a voltage from a reference voltage source 24 is impressed to a non-inverting input while the voltage is adjusted by a variable resistor 25. The output from the operational amplifier circuit 23 is led onto a line 11 and a voltage from the line 11 is inputted to the inverting circuit 12 to apply inversion with a voltage amplification factor of '-1'. The output of the inverting circuit 21 is led to the line 13, and a series circuit 14 comprising the load RL and the resistor Rs is connected between the lines 11 and 13. The inverting input of the operational amplifier circuit 23 is connected to the connecting point 15 between the load RL and the resistor Rs via the resistor R3. Thus, the current (i) is made independently of the load RL.