公开(公告)号：US20230418548A1

公开(公告)日：2023-12-28

申请号：US17846586

申请日：2022-06-22

Applicant: STMicroelectronics S.r.l.

Inventor： Francesco STILGENBAUER

IPC: G06F3/16

CPC classification number: G06F3/165

Abstract: An audio device includes a gain step selection circuit that receives a different requested gain value and an associated requested step size from each of a plurality of sources, compares each requested gain value to a same feedback gain value and generates a polarity based thereupon, performs step polarization on each requested step size as a function of the generated polarity therefor to thereby generate a plurality of step values, and outputs a least of the plurality of step values as an output step value. An accumulator circuit generates a current input gain value based upon the output step value and the feedback gain value, and then updates the feedback gain value to be equal to the current input gain value. A normalizing circuit multiplies an input data value by the current input gain value and applies a truncation function to a result thereof to produce an output data value.

公开(公告)号：US20240088844A1

公开(公告)日：2024-03-14

申请号：US18243754

申请日：2023-09-08

Applicant: STMicroelectronics S.r.l.

Inventor： Edoardo BOTTI ,  Francesco STILGENBAUER ,  Piero MALCOVATI ,  Edoardo BONIZZONI ,  Matteo DE FERRARI

IPC: H03F3/217 ,  H03F1/02 ,  H03M1/82 ,  H03M3/00

CPC classification number: H03F3/2175 ,  H03F1/0255 ,  H03M1/822 ,  H03M3/424 ,  H03F2200/03

Abstract: Signal processing is applied to a digital audio input signal to provide an analog audio output signal using a switching converter circuit driven by a pulse-width-modulated (PWM) signal. The analog audio output signal is sensed to provide an analog feedback signal. The signal processing that is applied includes: converting the digital audio input signal to producing an analog replica; producing an analog error signal indicative of a difference between the analog replica of the digital input signal and the analog feedback signal; converting the analog error signal to produce a digital error signal; digitally filtering the digital error signal to produce a filtered digital error signal; and generating the PWM signal from the filtered digital error signal.

公开(公告)号：US20230336136A1

公开(公告)日：2023-10-19

申请号：US17719613

申请日：2022-04-13

Applicant: STMicroelectronics S.r.l.

Inventor： Francesco STILGENBAUER ,  Paolo CACCIAGRANO ,  Giovanni GONANO

IPC: H03G3/34 ,  H04R3/00

CPC classification number: H03G3/344 ,  H04R3/00 ,  H04R2430/01 ,  H03G2201/103

Abstract: A digital audio playback circuit includes a noise shaping circuit configured to receive an input digital audio signal, and a digital to analog converter (DAC) configured to convert the input digital audio signal to a pre-amplified output analog audio signal according to a gain ramp defined by a gain control signal. A muting circuit is configured to compare input digital audio signal to a threshold and assert a mute control signal when the input digital audio signal is below the threshold. An analog gain control ramp circuit is configured to generate the gain control signal in response to the mute control signal to cause the gain ramp to ramp down. An amplifier is configured to amplify the pre-amplified output analog audio signal for playback by an audio playback device.

公开(公告)号：US20230421167A1

公开(公告)日：2023-12-28

申请号：US17846520

申请日：2022-06-22

Applicant: STMicroelectronics S.r.l.

Inventor： Francesco STILGENBAUER

IPC: H03M1/06

CPC classification number: H03M1/0668 ,  H03M1/0648 ,  H03M1/0626

Abstract: A signal processing circuit includes a filter generating a quantizer input signal from a noise shaping input signal and a quantizer output signal. A quantizer divides the quantizer input signal by a scaling factor to produce a noise shaping output signal and multiplies the noise shaping output signal by the scaling factor to produce the quantizer output signal. Receiver circuitry scales the quantizer output signal by a second scaling factor. A dynamic range optimization circuit compares a current value of the noise shaping input signal to a threshold value, lowers or raises the scaling factor in response to the comparison, and proportionally lowers or raises the scaling factor such that a ratio between the scaling factor and second scaling factor remains substantially constant.

公开(公告)号：US20230412129A1

公开(公告)日：2023-12-21

申请号：US18206331

申请日：2023-06-06

Applicant: STMicroelectronics S.r.l.

Inventor： Edoardo BOTTI ,  Francesco STILGENBAUER ,  Marco RAIMONDI ,  Elena CUSSOTTO

IPC: H03F3/217

CPC classification number: H03F3/2173 ,  H03F2200/03 ,  H03F2200/171 ,  H03F2200/351

Abstract: A switching circuit includes first and second half bridges supplying an electrical load via filter networks. During alternate switching sequences a first transistor pair (high-side in one half bridge and low-side in the other half bridge) is switched to a non-conductive state, and a second transistor pair (high-side in the other half bridge and low-side in the one half bridge) is switched to a conductive state. A current flow line is provided by an inductance, a first switch and a second switch between outputs of the half bridges. In a medium-high power mode, the first and second switches are in the conductive state between switching the first pair of transistors to the non-conductive state and the second pair of transistors to the conductive state. In a low or quiescent power mode, switching the first and second switches to the conductive state is refrained due to application of a longer delay.