公开(公告)号：JPH1155989A

公开(公告)日：1999-02-26

申请号：JP16715398

申请日：1998-06-15

Applicant: ST MICROELECTRON INC

Inventor： BRAMBILLA MASSIMILIANO ,  NGUYEN CHINH DAC ,  LEE EUGENE C

IPC: G11B19/22 ,  H02P6/24

Abstract: PROBLEM TO BE SOLVED: To completely brake a spindle motor, by generating a brake signal when a power supply signal represents that a voltage supply source is insufficient and a voltage at a filter capacitor is a threshold value or less, and braking the motor. SOLUTION: When a voltage supply source VSUPP is completed, a rotor continues rotating for inertial mass and generates a counter-EMF voltage. This counter-EMF voltage is applied to a filter capacitor 58, and the voltage across the capacitor 58 is maintained. A voltage across the capacitor 58 is dropped as the rotor is decelerated due to a frictional effect. And, if the voltage is lowered to a input threshold value or less, a timing circuit 100 supplies a logic '1' to its output terminal and starts braking. Thus, a delay occurs between the end of the voltage VSUPP and braking of a spindle motor 32. Hence, since the motor 32 is dynamically braked after the rotor is decelerated, it can be safely braked.

公开(公告)号：JPH1175390A

公开(公告)日：1999-03-16

申请号：JP18496798

申请日：1998-06-30

Applicant: ST MICROELECTRON INC

Inventor： CARLO BAATEMARA ,  MENEGOLI PAOLO ,  BRAMBILLA MASSIMILIANO

IPC: H02P1/52 ,  H02P6/20 ,  H02P23/00 ,  H02P7/62

Abstract: PROBLEM TO BE SOLVED: To improve a method and equipment for starting the rotation of a rotor in a multi-phase DC motor, by controlling the operation of a three-phase DC motor. SOLUTION: A microcontroller 40 controls drive currents in coils 8, 9, 10 through a serial interface 54, a sequencer 56 and a predriver circuit 58. The microcontroller 40 supplies data from a port 60 to the serial interface 54, and the serial interface 54 generates signals based on the data and supplies the signals to the sequencer 56. The sequencer 56 has a set of 8-bit registers, and each register retains information for giving instructions to the predriver circuit 58 for making driving transistors 13, 14, 15, 16, 18 and 20 to either conducting state or non-conducting state.