公开(公告)号：US20150280621A1

公开(公告)日：2015-10-01

申请号：US14733384

申请日：2015-06-08

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Mayank Garg ,  David Hernandez ,  Brandon J. Beckham ,  David J. Baldwin ,  Brett E. Forejt

IPC: H02P6/00 ,  G06F3/01 ,  G06F3/041 ,  H02P6/18

CPC classification number: H02P6/006 ,  G06F3/016 ,  G06F3/0416 ,  H02P6/182 ,  H02P7/00 ,  H02P7/025 ,  H02P25/02 ,  H02P25/032

Abstract: A method for driving a Linear Resonant Actuator (LRA) is provided. During a first off interval, the back-emf of the LRA is measured. During a first off interval, a timer is started when the back-emf reaches a predetermined threshold, and after a predetermined delay has lapsed following the back-emf reaching the predetermined threshold during the first off interval, the LRA is driven over a drive interval having a length and drive strength. A second off interval is entered following the drive interval, and during the second off interval, the back-emf of the LRA is measured. During the second off interval, the timer is stopped when the back-emf reaches the predetermined threshold. The value from the timer that corresponds to the duration between the back-emf reaching the predetermined threshold during the first off interval and the back-emf reaching the predetermined threshold during the second off interval determines the length.

Abstract translation: 提供了一种用于驱动线性谐振致动器（LRA）的方法。 在第一个关闭间隔期间，测量LRA的反电动势。 在第一关闭间隔期间，当反电动势达到预定阈值时，启动定时器，并且在第一关闭间隔期间在反电动势达到预定阈值之后经过预定延迟之后，LRA在驱动间隔 具有长度和驱动力。 在驱动间隔之后输入第二个关闭间隔，并且在第二个关闭间隔期间，测量LRA的反电动势。 在第二关闭间隔期间，当反电动势达到预定阈值时，定时器停止。 对应于在第一关闭间隔期间达到预定阈值的反电动势之间的持续时间的定时器的值和在第二关闭间隔期间达到预定阈值的反电动势确定长度。

公开(公告)号：US09628006B2

公开(公告)日：2017-04-18

申请号：US14613937

申请日：2015-02-04

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： David Hernandez ,  Gregory Charles Amidon ,  David John Baldwin ,  Brandon J. Beckham

IPC: H02P7/00

CPC classification number: H02P7/0094

Abstract: An apparatus includes a motor driver configured to drive a motor across a pair of input terminals to the motor and a current sense unit configured to sense the motor's electrical current amplitude. Further, an angular frequency extractor is operatively coupled to the motor driver and the current sense unit and configured to detect discontinuities in the motor's electrical current amplitude. The angular frequency extractor also is configured to determine a time period for one complete revolution of a rotor of the motor and to generate a feedback signal based on the determined period to control an angular frequency of the motor. The feedback signal may be used to adjust how the motor is being driven (e.g., to slow the motor down or speed it up).