Patent ID: 7310197

Claim:
A method for simultaneously measuring contact potential and slider body clearance in a hard disk drive, said method comprising: applying a plurality of direct current (DC) pulses between said slider body and a hard disk of a magnetic disk drive, wherein said plurality of direct current (DC) pulses are applied at a plurality of discrete locations on said hard disk, wherein each pulse of said plurality of direct current (DC) pulses comprise an equivalent voltage and duration; ceasing said applying a plurality of direct current (DC) pulses, measuring a contact potential voltage between said slider body and said hard disk at each of said plurality of discrete locations in response to applying said plurality of direct current (DC) pulses at said each of said plurality of discrete locations on said hard disk; and increasing the voltage of said plurality of direct current (DC) pulses at each of said plurality of discrete locations until a contact between said slider body and said hard disk at each of said plurality of discrete locations is detected, increasing said equivalent voltage and duration for each pulse; and measuring clearance of said slider body relative to said hard disk, said clearance measured at said contact potential voltage and said voltages for causing said contact.