MAGNETIC DISK MEMORY

摘要

A magnetic disk memory mounted thereon with a semiconductor integrated circuit device operated under a second voltage for applying a ground potential of a circuit to a disc-shaped magnetic storage medium and being kept at a positive potential at the free end of an arm to which an MR head is attached and centering around a first potential of the above circuit and under a third voltage kept at a negative potential, wherein the semiconductor integrated circuit device has built-in therein a bias circuit for biasing the above MR head to the vicinity of a voltage centering around the first voltage, and a lead amplifier which feedbacks a current slightly smaller than emitter currents of first and second amplifier transistors and kept in an opposite phase by using a current feedback circuit for supplying a read signal by the above MR head to the bases of the above first and second amplifier transistors and providing a capacitor between the emitters of the first and second amplifier transistors to receive their collector output signals, which reduces signal current components flowing into the above capacitor, and which receives output signals from the first and second amplifier transistors.