Patent ID: 11894810
Assignee: STMICROELECTRONICS S.R.L.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 5:
6. A hard disk drive comprising:
a sense resistor configured to perform sensing and control of fly height of a tip in the hard disk drive, the sense resistor having a first sense terminal and a second sense terminal, wherein a constant voltage and constant current are applied to the sense resistor based on, respectively, a selection of a voltage mode operation and a circuit mode operation; and
a first amplifier circuit comprising a first transistor, a first load resistor, a first capacitor, a first control circuit, and a first current generator, the first control circuit configured to selectively apply a negative bias voltage supply to the first transistor; and
a second amplifier circuit comprising a second transistor, a second load resistor, a second capacitor, a second control circuit, and a second current generator, the second control circuit configured to selectively apply a positive bias voltage supply to the second transistor,
wherein each of the first amplifier circuit and the second amplifier circuit is configured to:
receive input signals from the sense resistor, and
amplify the input signals in accordance with a variation in resistance at the sense resistor.