公开(公告)号：US12170103B2

公开(公告)日：2024-12-17

申请号：US18448737

申请日：2023-08-11

Applicant: STMicroelectronics International N.V.

Inventor： Paolo Pulici ,  Michele Bartolini ,  Enrico Sentieri ,  Enrico Mammei ,  Matteo Tonelli ,  Dennis Hogg

IPC: G11B5/60 ,  G11B21/10

Abstract: A system for determining a fly height includes a first head of a disk drive, a second head of the disk drive, a capacitive sensor circuit coupled to the first head and the second head, and a logic device coupled to the capacitive sensor circuit. The capacitive sensor circuit is configured to measure a first capacitance between the first head and the first disk, remove noise from the first capacitance using a second capacitance between the second head and the second disk, and based thereon determine a corrected first capacitance. The logic device is configured to determine the fly height between the first head and the first disk using the corrected first capacitance.

公开(公告)号：US20240005956A1

公开(公告)日：2024-01-04

申请号：US18448737

申请日：2023-08-11

Applicant: STMicroelectronics International N.V.

Inventor： Paolo Pulici ,  Michele Bartolini ,  Enrico Sentieri ,  Enrico Mammei ,  Matteo Tonelli ,  Dennis Hogg

IPC: G11B5/60

CPC classification number: G11B5/607 ,  G11B5/6017

Abstract: A system for determining a fly height includes a first head of a disk drive, a second head of the disk drive, a capacitive sensor circuit coupled to the first head and the second head, and a logic device coupled to the capacitive sensor circuit. The capacitive sensor circuit is configured to measure a first capacitance between the first head and the first disk, remove noise from the first capacitance using a second capacitance between the second head and the second disk, and based thereon determine a corrected first capacitance. The logic device is configured to determine the fly height between the first head and the first disk using the corrected first capacitance.

公开(公告)号：US20250112596A1

公开(公告)日：2025-04-03

申请号：US18480322

申请日：2023-10-03

Applicant: STMicroelectronics International N.V.

Inventor： Alessio Emanuele Vergani ,  Francesco Piscitelli ,  Michele Bartolini

IPC: H03F1/02 ,  H03K5/24 ,  H03K19/20

Abstract: According to an embodiment, an envelope detector circuit for detecting an envelope of a signal from a sensor in a pre-amplifier circuit of a hard disk drive is provided. The circuit includes a half-wave rectifier, a low-pass filter, and a differential full-wave rectifier. The half-wave rectifier receives a differential voltage from the sensor indicating a fly height of the hard disk drive and generates a pair of single-ended output waveforms based on the differential voltage. Each pair of single-ended output waveforms has a positive polarity for a half-cycle it passes through. The low-pass filter includes a first and a second low-pass filter. The low-pass filter allows low-frequency signals from the pair of single-ended output waveforms to pass through while attenuating or blocking higher-frequency signals. The differential full-wave rectifier reconstructs a differential signal from the low-pass filter while removing DC rectified components.

公开(公告)号：US12165680B1

公开(公告)日：2024-12-10

申请号：US18538724

申请日：2023-12-13

Applicant: STMicroelectronics International N.V.

Inventor： Enrico Sentieri ,  Paolo Pulici ,  Enrico Mammei ,  Michele Bartolini ,  Matteo Tonelli

IPC: G11B5/60

Abstract: A method for determining a fly height includes measuring a first differential voltage between a first head of a disk drive and a reference voltage with a first front end circuit, converting the first differential voltage to a first analog current signal with the first front end circuit, and converting the first analog current signal to a second differential voltage with a first back end circuit. The first front end circuit is coupled with the first head. The first back end circuit is coupled with the first front end circuit. The method further includes determining a first capacitance between the first head and a first disk of the disk drive based on the second differential voltage and determining the fly height between the first head and the first disk using the first capacitance.

公开(公告)号：US20250069623A1

公开(公告)日：2025-02-27

申请号：US18946503

申请日：2024-11-13

Applicant: STMicroelectronics International N.V.

Inventor： Paolo Pulici ,  Michele Bartolini ,  Enrico Sentieri ,  Enrico Mammei ,  Matteo Tonelli ,  Dennis Hogg

IPC: G11B5/60

Abstract: A system for determining a fly height includes a first head of a disk drive, a second head of the disk drive, a capacitive sensor circuit coupled to the first head and the second head, and a logic device coupled to the capacitive sensor circuit. The capacitive sensor circuit is configured to measure a first capacitance between the first head and the first disk, remove noise from the first capacitance using a second capacitance between the second head and the second disk, and based thereon determine a corrected first capacitance. The logic device is configured to determine the fly height between the first head and the first disk using the corrected first capacitance.