Analog and audio

Posted on November 24, 2014 at 12:52Hello, I built a system using a ad converter (PCM4202 from TI) and a sta311b DSP. I drive the power fets with the ffx pwm stage of the sta311b. When I measure the phase response of the hole system (without any dsp settings) I get a very bad phase plot. Is it possible to correct the phase with the speaker tune option? Can I measure the Phase and generate a speaker response file like I would do with a mems microphone? Thanks in advance.

Posted on November 28, 2014 at 09:04Hi, Is there tmeperature drift difference between the two types? Or is there any other difference between the two type,please? Thanks!

Posted on November 25, 2014 at 12:16As the STSpeakerTune technology is now freely available in the latest APWorkbench v2.1.0 here's a quick step-through list to assess the feature: Run APWorkbench (download it from http://www.st.com/apworkbench and install it)Select the ''Sound Terminal Amplifiers'' section in the Launch Wizard dialogSelect a digital amplifier with IIR processing capabilities, such as STA311B or STA369BWSGo to the ''Equalizer Editor'' page and open the ''speaker response'' browsing dialog (use the ''...'' button located in the ''SpeakerTune options'' group of controls.Browse to the location where the sample frequency response file is located, typically: C:\Program Files (x86)\STMicroelectronics\APWorkbench\DocumentsLoad the frequency response file, it will appear on the Equalizer

Posted on November 09, 2014 at 03:48Dear all, I had been trying really very hard to search by internet and or trying to call ST distributor searching for DATASHEETS of ESM7045DV, unfortunately I found nothing.  Is there anyone that could help me out please? Thank you in advance! I really appreciate. Best regards,   Hongya 2014 Nov.8 

Posted on October 15, 2014 at 06:04Hi,i'm an italian videomaker interested on MEMS micI want to record some audio using your Evaluation Kit (STEVAL-MKI126V1 + MKI129V3 connected to my laptop through the MKI138V1).I've installed APWorkbench on Windows 64bit running on Parallels Desktop.FTDI missing but i can run the app for the STSmartvoice Demo Kit.What i need is capturing sound from the 4 mics on the 129 board and mix them to a mono file.The main reason is to get a higher SNR for a better audio quality.Could you please show me how to send CH3 4 5 6 to only one OUT Channel?More. I can control the volume only of mic 4 and 5.It would be great to solve this problem before my shooting next week.Thanks so much.Michele #mki138v1-apworkbench-studiohub

Posted on November 10, 2014 at 01:20Hi     I try to add an external amplifier to STA350BW, the external amplifier work as subwoofer，but I realize that there are two type amplifiers: STA510A(DDX output)and STA510F(FFX output), I can't find any information about this two mode。 my question is：STA350BW must work with FFX amplifier？or both DDX and FFX amplifier？ 

Posted on November 07, 2014 at 07:59hello     I try to connect an external amplifier to STA350BW, the external amplifier work as subwoofer，but I realize that there are two amplifiers STA510A(DDX output)and STA510F(FFX output), I can't find any information about this two mode。 my question is：STA350BW must work with FFX amplifier？or both DDX and FFX amplifier？       

Posted on September 10, 2014 at 06:06Although there is any input singal,it still generate 40KHZ modulating wave output. Could tell me what could cause this? How can i solve this problem? Testing method as fellow: Power Supply: 24V/4Ohm test load: cement resistor(4Ohm/100W) #tda7498-modulating-wave-output

Posted on July 20, 2014 at 18:04Hello, first : can i use STA333 with filterless output (only snubber) ? (and sound quality ...better , than with filter ?) and in the APW gui, i cannot import speaker response (F5) - not working; is this only working, when active STA is connect or ..when ?

Posted on July 07, 2014 at 15:32Hello.If I connect the board to my computer it recognizes it and installs some drivers.It will after that show up as a ''STM Device in DFU Mode'' under USB controllers in the device manager. But in the APWorkbench there is no USB port to select under the ''MEMS Microphones Demo Kit'' menu.I tried this on both windows 7 and 8 64bit.Any way I can fix this? #mki138v1-apworkbench-staudiohub

Posted on February 07, 2014 at 10:08I've installed the APWorkbench suite but I'm getting the following message when launching the application: 'APWorkbench I/O warning: No FTDI driver found, APWLink communication will be disabled…..'. Can you please provide more explanation about?

Posted on July 03, 2014 at 17:33Is it possible to record multiple mic channels (more than stereo) over USB using the combination of STEVAL-MKI129V3, STEVAL-MKI138V1 and the STEVAL-MKI126V3? #steval-boards-for-mems-mics

Posted on January 16, 2014 at 17:19What is the STSmartVoice Demo Kit?

Posted on July 03, 2014 at 00:14Hello, I had a question of the best way to implement the supplemental +/- 20 VDC *supplemental* supply (i.e., not the +/- 40 VDC main supply). My 40 VDC supply is unregulated. Two thoughts were to use a voltage divider (off of the +/- 40 VDC supply), or even a high-current regulator on the +/- 40 VDC supply. If a voltage divider is acceptable, what is the  best way to minimize the static/idling current when the additional power isn't required ?Thank you,Mr. Amalfi #audio-amplifier-tda7294

Posted on May 06, 2014 at 00:07TS555CN is a low power version of NE555.TS555CN is made by STAll Datasheets of TS555CN say ''high output current capability''but there is no max output current given in any DataSheet!is the max output current better than with NE555 ?how much is it ?Is there a package of TS555 that can be cooled?thanksGerald Trost #timer-555

Posted on April 25, 2014 at 13:57Hi i'm currently using the STA350BW on the demonstration board do you have a  Schematic for 2 (half-bridge) channels + 1 (full-bridge) channel  2.1 mode including recommended component values?Thanks in advance

Posted on April 17, 2014 at 00:24Hi I have a question concerning the PCB routing of the TS4621ML headphone amplifier in 400um flip-chip package.  I have the STEVAL-CCA025V1 demoboard for the TS4621E part and looking at the gerber files for it it appears the inner balls of the package were routed by placing a via directly next to the ball pad but this would seem to violate the design guidelines in the datasheet for the part (which recommend a max 100um track from the pad).  I'd like to avoid using microvias due to cost and would thus like to receive some guidance concerning routing the inner balls of this package.Here is a screenshot of the gerbers for the demoboard to show what I'm talking about:

Posted on April 04, 2014 at 14:29HelloI've been working with STA310 to decode MPEG-1 Layer II compressed elementary streams but it is now obsolete. I would like to know if there is any new component able to decode MPEG-1 Layer II now. Looking at the STA013 datasheet I can see that it is capable of doing MPEG-1 Layer III but support for MPEG-1 Layer II is not specified. Could you assist me with this?Thank youRegards #sta013-sta310-mpeg-1-audio

Posted on April 09, 2014 at 12:03I am working with a STEVAL-MKI138V1, with a sta321mpl processor and mp34dt01 microphones. I have configured everything and I can control all the inputs, my problem is how can I choose the output channel, the output I2S channel.  I am using another software for recording the sound (setting the microphone board as input)  Any advice?? Thank you very much in advance.  I have configured everything and I can control all the inputs, my problem is how can I choose the output channel, the output I2S channel.  I am using another software for recording the sound (setting the microphone board as input)  Any advice?? Thank you very much in advance.

Posted on April 02, 2014 at 12:32Hey everyone. I am using a STM32F4 - Discovery board to read an analog value from a pressure sensor to convert it into depth. My problem is that the sensor that I need works with 0-5V and my STM32F4 works only with 3.3V. Is there any way to make the analog read module's reference an external 5V that I provide? #adc---external-voltage

Posted on April 03, 2014 at 20:56I am currently working a project to detect the version of STDP4020 firmware. I got all the data bytes of this firmware, can anybody give me some clue how to interpret them, particularly, which part tells the version number of this firmware?Attached is the data byte I got.Thanks a lot! #stdp4020

Posted on March 20, 2014 at 19:27Thanks for help, tried several things, cannot find the right way...

Posted on February 27, 2014 at 11:32For our industrial application, we implemented a STA013 to play sound files located on a SD card. We have to play background music and sometimes play some notification sound. So we send background music MP3 to STA013 and when we have to play a notification sound, we stop the music flow, to send to STA013 the notification MP3, and restart flow of the background music. This method works correctly, but we have some trouble on the change of MP3 flow : a glitch is often heard when the MP3 flow change. We assume its comes from the brutal change of flow. We search a solution, like void mp3 buffer of sta013, or a soft reset. To avoid to many calibration of sta013, every mp3 have been reencoded to have the same characteristics.Have you already met the problem ? Have you some idea to destroy this glitch ?

Posted on October 03, 2013 at 20:24Hello! i have a trouble with setting volume level in TDA7468. I use a wiring diagram as datasheet, and send setting to this IC using the C code:void writer(unsigned char adr_IC, unsigned char adr_reg,unsigned char data){i2c_start();i2c_write(adr_IC);i2c_write(adr_reg);i2c_write(data);i2c_stop();delay_ms(50);}writer (0x88,0x00,0x00); // input=in1writer (0x88,0x01,0x00);// input gaine=0 dBwriter (0x88,0x02,0x00); // surround=offwriter (0x88,0x03,0x00);// left volume=0dB maximumwriter (0x88,0x04,0x00);// right volume=0dB maximumwriter (0x88,0x05,0x77); //bass & treble = 0dBwriter (0x88,0x06,0x01); // MUTE=offwriter (0x88,0x07,0x00); // bass ALC=OFFbut the level of the output signal is significantly lower than the input signal. chip reacts to further change the tone level and vo

Posted on January 20, 2014 at 09:00Hello, in AP-Workbench and Datasheet, i did not found any Switch to generate ''Mono'' from 2-channel Input, with STA350BW Would this be possible using the PEQ? Thank you best regards, Florian Breu #mono-downmix-sta350bw #apworkbench-forum