Disk drive including preamplifier for perpendicular magnetic recording system

摘要

There is disclosed a disk drives of the perpendicular magnetic recording system capable of using a data channel of the longitudinal magnetic recording system. The drive has a preamplifier including a differentiation circuit which differentiates a read signal output from a read head. The preamplifier includes an adjusting circuit which adjusts low cut-off frequency for restricting waveform deformation of a read signal of rectangular waveform, as a front stage of the differentiation circuit.