Patent ID: 7130143

Claim:
An apparatus to measure MR head resistance, the apparatus comprising: a measurement module configured to measure a reference voltage across a reference resistance while applying a reference current to the reference resistance and measure a test voltage across a first biasing resistor, a MR head assembly, and a second biasing resistor connected in series while applying the reference current to the first biasing resistor, the MR head assembly, and the second biasing resistor; and a computation module configured to calculate the resistance of the MR head assembly as R h =((R ref V hb )/V ical )−(R b1 +R b2 ) where Rh is the resistance of the MR head assembly, Rref is the resistance of the reference resistance, Vical is the reference voltage, Vhb is the test voltage, Rb1 is the resistance of the first biasing resistor and Rb2 is the resistance of the second biasing resistor.