Patent ID: 8107181
Filing Date: 2012-01-31
Classification: G11B

Abstract:
1. 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 MR head assembly resistance from the reference voltage, the test voltage, the reference resistance, and the resistances of the first and second biasing resistors; wherein the computation module calculates the resistance of the MR head assembly as a function of a ratio of the reference current divided by the reference current such that a measurement of the reference current is not a factor in the calculation.