High-density recording method for hard disk drives and a pre-amplifier circuit suitable for use with same

A magnetic recording method for recording data by changing magnetization directions of a magnetic recording medium, said method comprising:

• recording ternary data in a first area on said recording medium magnetized for the intensity of magnetic flux detected by a read head from the magnetic recording medium to be −1;
• recording ternary data in a second area on said recording medium magnetized for the intensity of magnetic flux detected by the read head from the magnetic recording medium to be 1;
• and
• recording ternary data in a third area on said recording medium magnetized for the intensity of magnetic flux detected by the read head from the magnetic recording medium to be 0.

A pre-amplifier circuit applying a write current to a write head to record data having a minimum write width corresponding to at least a detection width of a read head, the pre-amplifier circuit comprising:

• a direct current (DC) signal generator generating a DC signal having a predetermined amplitude;
• a first switch circuit for applying the DC signal from said DC generator to the write head in a first direction during a period in which the data to be recorded has a first value;
• a second switch circuit for applying the DC signal from said DC generator to the write head in a second direction opposite to the first direction during a period in which the data to be recorded has a second value;
• a high frequency signal generator generating a high frequency signal having a higher frequency than a write frequency corresponding to the minimum write width;
• and
• a third switch circuit for applying the high frequency signal to the write head during a period in which the data to be recorded has a third value.