TDA7468 volume control

eferguson · ‎2013-10-03

Posted on October 03, 2013 at 20:24

Hello! 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=in1

writer (0x88,0x01,0x00);// input gaine=0 dB

writer (0x88,0x02,0x00); // surround=off

writer (0x88,0x03,0x00);// left volume=0dB maximum

writer (0x88,0x04,0x00);// right volume=0dB maximum

writer (0x88,0x05,0x77); //bass & treble = 0dB

writer (0x88,0x06,0x01); // MUTE=off

writer (0x88,0x07,0x00); // bass ALC=OFF

but the level of the output signal is significantly lower than the input signal. chip reacts to further change the tone level and volume level to down. please, explain how to set the volume level

#tda7468

Nickname14663_O · ‎2014-02-14

Posted on February 14, 2014 at 13:15

Hello Ellis,

This forum is dedicated to operational amplifiers, comparators and current sensing products.

In order to be more efficient with appropriate answers, another e2e forum has been created for audio amplifiers.

In order to have an accurate answer by our audio support team, would it be possible to copy/paste your question to the related forum please ?

Here is the hyperlink shortcut :

https://my.st.com/public/STe2ecommunities/analog/Lists/Audio%20Amplifiers/AllItems.aspx

Sorry for the inconvenience.

Best regards,

Sylvain

Nickname1623_O · ‎2014-02-17

Posted on February 18, 2014 at 08:36

hi Ellis ,

please check the output waveform with one channel audio input signal only, if the output is normal, please modify surround register setting data to 0x18 hex from 0x00 hex.

thanks