Magneto resistive voltage biasing scheme with fast recovery and maximum dynamic range

• Main Author: VOO THART FAH
• Format: Patent
• Language: English
• Published: 10.04.2012
• Subjects: INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS

A system and method for providing a fast recovery for voltage bias applied to an MR sensor, when a voltage is applied to the MR sensor very quickly while the MR sensor transitions from an idle or sleep state to an active state includes an apparatus and method for adjusting the voltage and range applied to the MR sensor. The apparatus includes a circuit having a current biasing circuit for supplying a current bias to a transducer, a voltage biasing circuit configured to supply a voltage bias to a transducer, and a charge pump for maintaining the current bias and the voltage bias at the maximum range so that the voltage at the transducer is maximized. The method includes specifying the magneto resistive biasing voltage, measuring a resistance of the magneto resistive sensor, setting an internal reference resistance value to be near the measured resistance of the magneto resistive sensor, determining a code that specifies the amount of current that flows through the magneto resistive sensor, flowing current through the magneto resistive sensor by turning on a digital to analog converter adjustable resistor.