公开(公告)号：US20180109213A1

公开(公告)日：2018-04-19

申请号：US15296031

申请日：2016-10-17

Applicant: Texas Instruments Incorporated

Inventor： Sooping Saw ,  Anuj Jain ,  Jeffrey Okyere ,  Wen Chao Qu

IPC: H02P8/32 ,  H02P8/34 ,  H02P8/12 ,  H02P6/08

CPC classification number: H02P8/32 ,  H02P6/085 ,  H02P8/12 ,  H02P8/34

Abstract: A stepper motor control system includes stepper motor error reduction. For example, first and second power switches respectively energize and de-energize a stepper motor coil during each cycle for pulse-width modulating (PWM) the coil current. During a cycle including a zero crossing microstep, a calibrator detects a type of a body diode effect that occurs in the second power switch when the second switch stops de-energization of the coil. A selected offset is adjusted in response to the type of detection of the body diode effect of the second power switch. Adjusting the selected offset controls the trigger time for a comparator for comparing an offset reference voltage to a motor voltage developed in response to the coil current. Progressively adjusting the selected offset over successive cycles compensates for delays of components in the PWM control loop and reduces errors resulting from, for example, process, voltage, and temperature variations.

公开(公告)号：US09791521B2

公开(公告)日：2017-10-17

申请号：US14670078

申请日：2015-03-26

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Michael Edwin Butenhoff ,  Keith Ryan Green ,  Anuj Jain

IPC: G01R33/06 ,  G01R33/00 ,  G01R33/07

CPC classification number: G01R33/0023 ,  G01R33/072

Abstract: A method for verifying an operation of a Hall-effect sensor without an applied magnetic field. The method can include providing a bias signal to a first pair of terminals of a Hall-effect element, applying a Hall current signal to a second pair of terminals of the Hall-effect element, measuring a Hall output voltage across the second pair of terminals and comparing the measured Hall output voltage to an expected Hall output voltage that would be provided by a corresponding applied magnetic field.

公开(公告)号：US09705436B2

公开(公告)日：2017-07-11

申请号：US14960164

申请日：2015-12-04

Applicant: Texas Instruments Incorporated

Inventor： Stephen John Fedigan ,  Anuj Jain ,  David Patrick Magee

IPC: H02K29/08 ,  H02P6/16

CPC classification number: H02P6/16 ,  H02P21/06

Abstract: A motor control system for a permanent magnet synchronous motor (PMSM) uses two linear Hall devices to produce a first signal indicative of a strength of a first magnetic field component produced by a set of rotor magnets and to simultaneously produce a second signal indicative of a strength of second magnetic field component produced by the rotor magnets that is approximately orthogonal to the first magnetic field component. An angular position and angular velocity of the rotor is calculated based on the first signal and the second signal. A plurality of phase signals is produced based on the calculated angular position and angular velocity. Current in a plurality of field windings of the motor is controlled using the plurality of phase signals.