Patent ID: 6914738

Claim:
A disk storage apparatus in which writing of data onto a discoid recording medium and reading of data from the recording medium are carried out by a head, comprising: a write driver which supplies a write current to the head in accordance with write data, wherein the write driver includes a current source which generates the write current, and a bridge circuit containing a pair of first transistors and a pair of second transistors, the pair of first transistors supplying the write current generated by the current source to the head in a first direction in accordance with a first control signal corresponding to the write data, the pair of second transistors supplying the write current generated by the current source to the head in a second direction opposite to the first direction in accordance with a second control signal corresponding to the write data; a temperature sensor which detects the environmental temperature of the disk storage apparatus; a controller which controls an overshoot current included in the write current supplied from the write driver to the head in accordance with the temperature detected by the temperature sensor, wherein the controller includes an overshoot controller which controls the overshoot included in the write current supplied from the write driver to the head, and a main controller which controls the overshoot controller in accordance with the temperature detected by the temperature sensor; a first pulse generation circuit which generates a first pulse after elapse of a delay time determined from an output voltage of the temperature sensor and outputs it to the overshoot controller every time the first control signal changes its state from a first logic state to a second logic state, and whose delay time can be varied; and a second pulse generation circuit which generates a second pulse after elapse of a delay time determined from an output voltage of the temperature sensor and outputs it to the overshoot controller every time the second control signal changes its state from the first logic state to the second logic state, and whose delay time can be varied, wherein the main controller sets in the first and second pulse generation circuits a delay time determined by the parameter value corresponding to the temperature detected by the temperature sensor, and wherein the overshoot controller controls the overshoot current by controlling the base potential of a transistor on the outflow side of the write current in the pair of first transistors in accordance with a pulse output from the first pulse generation circuit, and by controlling the base potential of a transistor on the outflow side of the write current in the pair of second transistors in accordance with a pulse output from the second pulse generation circuit.