CPC H03F 1/26 (2013.01) [H03F 3/45192 (2013.01)] | 20 Claims |
1. A circuit for sensing and controlling a fly height of a tip in a hard disk drive comprising the circuit, an input of the circuit coupled to a sense resistor at a first sense terminal and a second sense terminal, the circuit comprising:
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, and a second current generator,
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.
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