TDA7492E - analog input section.

[Przemex]

Hello,

I have two questions regarding TDA7492E amp. 

1. What is the common voltage for audio inputs? 
2. What is the maximum usable voltage on audio inputs? I would like to increase amplitude by op-amps, not the amp gain. 

Thank you and best regards,
Przemek

[Peter BENSCH]

Welcome @Przemex, to the community!

Both questions can be answered together: the permissible input voltage range is -0.3V...4.6V. If the range below 0V is ignored, the AC input voltage may therefore have a peak-peak of 4.6V, typically coupled via a capacitor.

Hope that helps?

Regards
/Peter

[Przemex]

Hello and thank you Peter!

I was wondering about this value (4.6V) because value is in the absolute maximum ratings table - voltage which should not damage device permanently. I can only guess that the mid point (bias) is 1,65V (3,3/2) and to keep symetry and unclipped signal, 3.3 V is maximum. However as I mention - it's only guessing because there is no information about it in datasheet and I don't have PCB yet :)

All the best!
Przemek

[Peter BENSCH]

You asked about the highest voltage, which is indeed specified in the absolute max ratings. Of course, this value must not be exceeded under any circumstances, otherwise there is a risk of losing the warranty or even defects in the device.

If the output voltage of the previous device is 3.3V because of its supply voltage, your assumption is correct. However, you do not need to add a DC offset because this is done via the coupling capacitor.

Good luck!
/Peter