Method of verifying preamplifier circuit functions, and magnetic record regeneration apparatus using the same

A magnetic record regeneration apparatus, comprising:

• a magnetic head for performing writing and readout of data into and from a recording medium;
• and
• a preamplifier circuit with a write system which sends write currents corresponding to write data to the magnetic head and a read system which receives readout currents of the magnetic head, the preamplifier circuit comprising, in the write system:
• a write driver;
• a current-voltage conversion circuit for converting the write current from the write driver into a corresponding voltage;
• a waveform shaping circuit for converting the output voltage from the current-voltage conversion circuit into a full-wave rectified waveform;
• a peak-hold circuit for holding a peak value of the output from the waveform shaping circuit;
• a filter circuit for outputting an average voltage of the output from the waveform shaping circuit;
• and
• a determination circuit for determining that the write driver is abnormal based on each output status of the peak-hold circuit and the filter circuit.

A method of verifying normality of a preamplifier circuit in a magnetic record regeneration apparatus having a write system which sends write currents corresponding to write data to a magnetic head performing writing and readout of data into and from a recording medium and a read system which receives readout currents of the magnetic head, the method comprising the steps of:

• converting the write current from the write driver in the write system into a corresponding voltage;
• converting the converted voltage into a full-wave rectified waveform;
• holding a peak value of the converted full-wave rectified waveform;
• outputting an average voltage of the converted full-wave rectified waveform;
• and
• determining that the write system is abnormal based on the peak value and the average voltage.