公开(公告)号：ITVA990020D0

公开(公告)日：1999-07-16

申请号：ITVA990020

申请日：1999-07-16

Applicant: ST MICROELECTRONICS SRL

Inventor： DEMICHELI MARCO ,  BOLLATI GIACOMINO ,  DEMICHELI DAVIDE ,  MARCHESE STEFANO

IPC: G11B20/10

Abstract: A method is provided for defining programmed values of the boost and cut-off frequency parameters of a low pass filter of pre-equalization, of a read channel for a magnetic medium mass memory device, to ensure optimal functioning conditions of the adaptive filter of final equalization. The method includes pre-programming instantaneous digital values of the boost and cut-off frequency parameters of the low pass filter of pre-equalization for each magnetic medium, as a function of purposely sensed instantaneous operating parameters of the adaptive filter that carries out the definitive equalization of the signal during a trim scanning of the magnetic medium.

公开(公告)号：DE69515869T2

公开(公告)日：2000-12-07

申请号：DE69515869

申请日：1995-09-14

Applicant: ST MICROELECTRONICS SRL ,  CONS RIC MICROELETTRONICA

Inventor： BRUCCOLERI MELCHIORRE ,  DEMICHELI DAVIDE ,  DEMICHELI MARCO ,  PATTI GIUSEPPE

IPC: H03G3/30 ,  G11B5/02 ,  H03G1/00 ,  H03G3/20

Abstract: The circuit described comprises a double half-wave rectifier (DHWR) connected to the outputs of the differential amplifier (VGA) in order to produce two quantities dependent on the amplitudes of the half-waves of the output signal of the amplifier (VGA), two comparators (COMP1, COMP2) each having an input (IN+1, IN+2) connected to an output (OUT1, OUT2) of the rectifier (DHWR) and a reference input (IN-1, IN-2) in order to produce respective output signals when the amplitudes of the respective half-waves are greater than the levels applied to the reference inputs (IN-1, IN-2), and processing means (Str1, A1, R1, Str2, A2, R2, C) for generating a signal for regulating the gain of the amplifier in dependence on the durations of the output signals of the two comparators. The circuit may advantageously be used when the signal to be amplified (v+, v-) is not symmetrical.

公开(公告)号：DE69515869D1

公开(公告)日：2000-04-27

申请号：DE69515869

申请日：1995-09-14

Applicant: ST MICROELECTRONICS SRL ,  CONS RIC MICROELETTRONICA

Inventor： BRUCCOLERI MELCHIORRE ,  DEMICHELI DAVIDE ,  DEMICHELI MARCO ,  PATTI GIUSEPPE

IPC: H03G3/30 ,  G11B5/02 ,  H03G1/00 ,  H03G3/20

Abstract: The circuit described comprises a double half-wave rectifier (DHWR) connected to the outputs of the differential amplifier (VGA) in order to produce two quantities dependent on the amplitudes of the half-waves of the output signal of the amplifier (VGA), two comparators (COMP1, COMP2) each having an input (IN+1, IN+2) connected to an output (OUT1, OUT2) of the rectifier (DHWR) and a reference input (IN-1, IN-2) in order to produce respective output signals when the amplitudes of the respective half-waves are greater than the levels applied to the reference inputs (IN-1, IN-2), and processing means (Str1, A1, R1, Str2, A2, R2, C) for generating a signal for regulating the gain of the amplifier in dependence on the durations of the output signals of the two comparators. The circuit may advantageously be used when the signal to be amplified (v+, v-) is not symmetrical.

公开(公告)号：DE69625192D1

公开(公告)日：2003-01-16

申请号：DE69625192

申请日：1996-08-07

Applicant: ST MICROELECTRONICS SRL

Inventor： BRUCCOLERI MELCHIORRE ,  DEMICHELI MARCO ,  DEMICHELI DAVIDE ,  PATTI GIUSEPPE

IPC: G11B5/55 ,  G11B5/596 ,  G11B21/10 ,  G11B5/00

Abstract: A servo-demodulator for a pair of alternating signals generated by a magnetic disc read head and indicative of the position of the read head in relation to the centre of a recorded track, comprising a peak detector (5) for successively and individually sampling the amplitude of each of a plurality of peaks of the said pair of alternating signals, and a capacitor (9) periodically connected to the output of the peak detector (5) by a control logic (7) for deriving a weighted average of the various successively sampled amplitudes, obtaining an averaged measure of amplitude with high immunity to noise.

公开(公告)号：ITVA990020A1

公开(公告)日：2001-01-16

申请号：ITVA990020

申请日：1999-07-16

Applicant: ST MICROELECTRONICS SRL

Inventor： DEMICHELI MARCO ,  BOLLATI GIACOMINO ,  DEMICHELI DAVIDE ,  MARCHESE STEFANO

IPC: G11B20/10

Abstract: A method is provided for defining programmed values of the boost and cut-off frequency parameters of a low pass filter of pre-equalization, of a read channel for a magnetic medium mass memory device, to ensure optimal functioning conditions of the adaptive filter of final equalization. The method includes pre-programming instantaneous digital values of the boost and cut-off frequency parameters of the low pass filter of pre-equalization for each magnetic medium, as a function of purposely sensed instantaneous operating parameters of the adaptive filter that carries out the definitive equalization of the signal during a trim scanning of the magnetic medium.

公开(公告)号：IT1313390B1

公开(公告)日：2002-07-23

申请号：ITVA990020

申请日：1999-07-16

Applicant: ST MICROELECTRONICS SRL

Inventor： DEMICHELI MARCO ,  BOLLATI GIACOMINO ,  DEMICHELI DAVIDE ,  MARCHESE STEFANO

IPC: G11B20/10

Abstract: A method is provided for defining programmed values of the boost and cut-off frequency parameters of a low pass filter of pre-equalization, of a read channel for a magnetic medium mass memory device, to ensure optimal functioning conditions of the adaptive filter of final equalization. The method includes pre-programming instantaneous digital values of the boost and cut-off frequency parameters of the low pass filter of pre-equalization for each magnetic medium, as a function of purposely sensed instantaneous operating parameters of the adaptive filter that carries out the definitive equalization of the signal during a trim scanning of the magnetic medium.