We are having difficulties in achieving unipolar configuration for headset connection and associated MICBIAS of 2.5V
Below are the configurations we have done to set the MICBIAS:
Intended operation |
Register/s Updated |
Bit/s Updated in the register |
Bit/s Value |
Power-down MICBIAS |
Page 1 / Register 51: MICBIAS Configuration Register |
D6 |
0 |
Set MICBIAS to 2.5V |
Page 1 / Register 10: Common Mode Control Register |
D6 |
0 |
Page 1 / Register 51: MICBIAS Configuration Register |
D5-D4-D3 |
1-0-1 |
|
Power-up MICBIAS |
Page 1 / Register 51: MICBIAS Configuration Register |
D6 |
1 |
We have set the following: DRVdd_HP = 3.3V, AVdd = 1.8V, VNEG = GND
With the above configuration, we observed MICBIAS of 3.3V instead of the anticipated 2.5V.Then we tried to set MICBIAS to other possible values but observed that it is always equal to the source(AVdd or DRVdd_HP) selected to generate the MICBIAS i.e., either 1.8V or 3.3V.
For further detail, I have also attached details of all the other configurations that we have done.
Thanks
TLV320AIC3256 CodecConfigurations.xlsx