HEAD POSITIONING CIRCUIT

PURPOSE:To perform the head positioning smoothly in a short time, by providing a means to interpolate a signal obtained from a digital-to-analog conversion means converting the number of tracks to an objective position to an analog value with a smoother waveform obtained from a position signal on a data plane of the disc. CONSTITUTION:The number of tracks X to the objective track enters a D/A converter 3 from a latch circuit 1 and is converted into an analog value, and the smoother signal is applied with an adder 6. The smoother signal is generated from interpolation signal generators 30 and 33 by using a data plane position signal, and the changeover of the two smoother signals is made with a switching signal S with an analog switch 19, and the generator 30 is selected if the position of the head is apart from =1/4 track from the objective position, and the generator 33 is selected from the objective position 1/4 to the objective position.