公开(公告)号：US09697706B2

公开(公告)日：2017-07-04

申请号：US14955553

申请日：2015-12-01

Applicant: Texas Instruments Incorporated

Inventor： Mandy Barsilai ,  David Hernandez ,  Mark Stephen Toth

IPC: G08B6/00 ,  G06F3/01

CPC classification number: G08B6/00 ,  G06F3/016

Abstract: Disclosed examples include methods and circuits to drive a haptic actuator, in which a single input signal from a host device has a first state representing a command to drive the actuator and a second state representing a command to stop the actuator. A control circuit provides a drive control signal to a driver circuit to drive the haptic actuator in response to the control signal transitioning to the first state, and to stop the haptic actuator in response to the control signal transitioning to the second state. A timer circuit places the circuit in a low power mode a predetermined time after the control signal transitions to the second state, or the control circuit places the circuit in the low power mode in response to a feedback signal indicating that the actuator has reached a stopped condition.

公开(公告)号：US11503404B1

公开(公告)日：2022-11-15

申请号：US17362650

申请日：2021-06-29

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： David Hernandez ,  Supriyo Palit

IPC: H04R3/00 ,  H03F3/183

Abstract: A system includes a feedforward path coupled to a signal input. The system also includes a speaker coupled to the feedforward path. The system includes a back electromotive force (BEMF) extractor coupled to the speaker, where the BEMF extractor has a first input, a second input, and an output. The BEMF extractor includes a first summing point coupled to the first input. The BEMF extractor includes a resistor amplifier coupled to the second input and the first summing point. The BEMF extractor includes a high pass filter coupled to the second input and to an inductor amplifier. The BEMF extractor also includes a low pass filter coupled to the first summing point. The BEMF extractor includes a second summing point coupled to the low pass filter, the inductor amplifier, and the output.

公开(公告)号：US11374522B2

公开(公告)日：2022-06-28

申请号：US16906364

申请日：2020-06-19

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： David Hernandez ,  Supriyo Palit

IPC: H02P25/034 ,  G05B19/4155 ,  H02P23/00

Abstract: Disclosed embodiments include an apparatus for closed loop control of a linear resonant actuator comprising a motor drive circuit configured to provide a motor drive signal, a current and voltage sensing circuit coupled to the output terminal of the motor drive circuit and across the motor, and having current sense and a voltage sense outputs. A resonant frequency and back emf extraction circuit receives the current sense and voltage sense outputs, and outputs a resonant frequency signal output and a measured back emf signal output. An actuator model circuit has inputs coupled to the output of the motor drive circuit, the resonant frequency signal output, and a mechanical system quality factor signal generated by an adaptation circuit having an input coupled to the error summing circuit output. The error summing circuit has inputs coupled to the output of the actuator model and the measured back emf signal.

公开(公告)号：US11121662B2

公开(公告)日：2021-09-14

申请号：US16856490

申请日：2020-04-23

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Supriyo Palit ,  David Hernandez

IPC: H02P25/06

Abstract: Disclosed embodiments include a method for closed loop phase tracking comprised of determining a first estimated resonant frequency, generating a motor drive signal at the first estimated resonant frequency and applying the motor drive signal to a motor, measuring current and voltage of the motor drive signal, and filtering the measurements of current and voltage of the motor drive signal. The phase difference between the filtered current and voltage waveforms is measured and a second estimated resonant frequency is calculated. The generated motor drive frequency is adjusted to equal the second estimated resonant frequency.

公开(公告)号：US09520822B2

公开(公告)日：2016-12-13

申请号：US13871191

申请日：2013-04-26

Applicant: Texas Instruments Incorporated

Inventor： David Hernandez ,  Mayank Garg ,  David J. Baldwin ,  Brandon James Beckham

IPC: H02P7/29 ,  H02P25/02 ,  H02P6/18 ,  G06F3/00

CPC classification number: H02P25/032 ,  H02P6/182

Abstract: Circuits and methods for driving ERM motors are disclosed herein. An embodiment of the circuit includes an input, wherein an input signal is receivable at the input and a back EMF signal. The circuit operates in a closed loop mode when the back EMF signal is less than a lower threshold value and the difference between the value of the input signal and the back EMF signal indicates that the velocity of the motor needs to increase. The circuit operates in an open loop mode when the back EMF signal is greater than a high threshold value and the difference between the value of the input signal and the back EMF signal indicates that the velocity of the motor needs to increase.

Abstract translation: 本文公开了用于驱动ERM电动机的电路和方法。 电路的实施例包括输入，其中输入信号可在输入端接收，反馈EMF信号。 当反电动势信号小于下限阈值时，电路工作在闭环模式，而输入信号与反电动势信号之间的差异表示电动机的速度需要增加。 当反电动势信号大于高阈值时，电路工作在开环模式，输入信号和反电动势信号之间的差值表示电动机的速度需要增加。

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：US11316507B2

公开(公告)日：2022-04-26

申请号：US17364489

申请日：2021-06-30

Applicant: Texas Instruments Incorporated

Inventor： David Hernandez ,  David Patrick Magee ,  Mohit Chawla ,  James Kelly Griffin

IPC: H03K7/08

Abstract: Techniques are provided herein for generating PWM signals. Furthermore, a direct-drive method is disclosed in which a PWM signal is generated as a differential signal made up of OUTP and OUTN signals, where OUTP is a copy of OUTN but shifted in time by half a period. The PWM signal is generated by passing each of an input period and an input duty cycle through corresponding sigma-delta circuits to generate a refined period and a refined duty cycle, respectively. In some example cases, a threshold mapper uses a lookup table (LUT) or similar mechanism to select timing thresholds for rise times and fall times for each of the OUTP and OUTN signals, where the timing thresholds are selected based on the refined period and the refined duty cycle. In some example cases, a pulse generator generates the OUTP and OUTN signals based on the timing thresholds.

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).

公开(公告)号：US20150204925A1

公开(公告)日：2015-07-23

申请号：US14601785

申请日：2015-01-21

Applicant: Texas Instruments Incorporated

Inventor： David Hernandez ,  Mandy Barsilai

IPC: G01R27/02 ,  G01R31/34

CPC classification number: G01R27/02 ,  G01R31/2829 ,  G01R31/343

Abstract: A method, apparatus and a system for a Linear Resonant Actuator (LRA) real time impedance tracking. The method includes extracting the Back Electro-Motive Force (BEMF) voltage from a driver's load current by determining a current multiplying factor utilizing a Least Mean Square (LMS) algorithm and introducing an error function to control the gain of the load current and isolate the BEMF.

Abstract translation: 线性谐振执行器（LRA）实时阻抗跟踪的方法，装置和系统。 该方法包括通过使用最小均方（LMS）算法确定电流倍数，并引入误差函数来控制负载电流的增益，从驱动器的负载电流中提取反电动势（BEMF）电压，并隔离 BEMF。

公开(公告)号：US11470434B2

公开(公告)日：2022-10-11

申请号：US17319061

申请日：2021-05-12

Applicant: Texas Instruments Incorporated

Inventor： David Hernandez ,  Amit Goyal

IPC: H04R29/00 ,  H04R9/06 ,  H04R3/00 ,  G01K13/00

Abstract: A system for determining the temperature of a voice coil of a speaker includes a first pre-emphasis filter which has an input coupled to receive a digitized current sense signal. The first pre-emphasis filter applies a gain to signal components at a selected frequency band and provides a pre-emphasized current sense signal. The system includes a second pre-emphasis filter which has an input coupled to receive a digitized voltage sense signal. The second pre-emphasis filter applies a gain to the signal components at the selected frequency band and provides a pre-emphasized voltage sense signal. The system includes a first quantizer module configured to map the pre-emphasized signal to a quantized current sense signal, and includes a second quantizer module configured to map the pre-emphasized voltage sense signal to a quantized voltage sense signal.