For me TDA7449L is a chip with analog functions. So I am concern on how to lay its pcb layout as part of embedded system in order to avoid noise/buzzing sound
you are right! a hybrid analog + I2C control signal is a bit difficult to do the PCB with respect to GND system. When you access the TDA7449 via I2C, you will hear the bit stream on the speaker. But with rules on PCB design of single point GND for analog and multi-point GND on digital - isolation component like inductor or low ohmic value resistor, you can optimized the co-existence of hybrid system, its more a trial and error GND, cut or connect PCB track during the test to optimized the noise. Sharing of V+ also for the MCU and TDA7449 matters - follow rules on Hardware and PCB design can help, for my project the Tone Control board is separate from the MCU and thus the I2C cable plays a lot -- twist it to immume to noise. Cheers!
