公开(公告)号：US20220080458A1

公开(公告)日：2022-03-17

申请号：US17475886

申请日：2021-09-15

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Supriyo PALIT ,  James Kelly GRIFFIN ,  David Patrick MAGEE

IPC: B06B1/02 ,  G02B27/00 ,  B08B7/02 ,  B08B13/00

Abstract: In an example, a method includes providing a pulse-width modulation (PWM) excitation signal to a piezo transducer via a transmit path. The method also includes collecting a block of samples of a current and a voltage at the piezo transducer, where the block of samples is collected in sub-blocks of samples between interrupts in a receive path. The method includes processing each sub-block of samples separately from other sub-blocks of samples. The method also includes, responsive to the sub-blocks of the block of samples being processed, analyzing the block of samples. The method includes, responsive to the analysis, modifying the PWM excitation signal.

公开(公告)号：US20210150865A1

公开(公告)日：2021-05-20

申请号：US16895701

申请日：2020-06-08

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Kevin Selva Prasanna VALANARASU ,  Supriyo PALIT

IPC: G08B6/00 ,  H04R3/04 ,  G06F3/16

Abstract: A method includes converting an audio signal of a current time period to a frequency domain to produce a set of frequency coefficients. For each of the frequency coefficients, the method includes computing a gradient of that frequency coefficient's magnitude relative to a magnitude of the same frequency coefficient from a previous time period. The method then includes summing the gradients computed for the set of frequency coefficients to produce a sum value, and then generating a haptic signal based on the sum value.

公开(公告)号：US20200288242A1

公开(公告)日：2020-09-10

申请号：US16856350

申请日：2020-04-23

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Supriyo PALIT ,  Abhishek SINGH ,  Kevin Selva Prasanna VALANARASU

IPC: H04R3/00 ,  H03F3/181 ,  H03G3/30

Abstract: An audio circuit includes an amplifier, a voltage sensor, a current sensor, and an excursion control circuit. The voltage sensor is coupled to an output of the amplifier. The current sensor is coupled to the output of the amplifier. The excursion control circuit is coupled to the amplifier, the voltage sensor, and the current sensor. The excursion control circuit includes back electro-magnetic force (EMF) measurement, a back-EMF model, and excursion protection. The back-EMF measurement is to measure back electro-magnetic force of a speaker based on voltage measurements received from the voltage sensor and current measurements received from the current sensor. The back-EMF model is updated based on measurements of the back-EMF and is converted to an excursion model. The excursion protection is to limit amplitude of audio signal provided to the amplifier based on the excursion model of the speaker and amplitude of an audio input signal.

公开(公告)号：US20190182589A1

公开(公告)日：2019-06-13

申请号：US16041955

申请日：2018-07-23

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Supriyo PALIT

IPC: H04R3/00 ,  H03F3/68 ,  H03F3/187 ,  H04R29/00

Abstract: A system includes a filter circuit configured to adjust digitized audio signal values based on filter parameters. The system also includes a filter parameter selection circuit configured to determine an audio signal bandwidth estimate based on back-EMF analysis and to supply different sets of filter parameters to the filter circuit based on the audio signal bandwidth estimate and a predetermined threshold. The system also includes a digital-to-analog converter (DAC) configured to convert an output of the filter circuit into an analog audio signal to be amplified.