A related question is a question created from another question. When the related question is created, it will be automatically linked to the original question.
If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.
Normal mode has both the PDN and reset pins set high (so the device is not in reset and not in power down mode) with the test conditions noted above the table in the datasheet (TA = 25°, PVCC_x = 18 V, DVDD = AVDD = 3.3 V, RL= 8 Ω, BTL AD mode, fS = 48 kHz).
What current consumption data are you measuring on your device and looking for? Is the 100mA @ 12V that you measured the PVCC supply current or the 3.3V supply current or the sum of the currents in both supplies?
I am not sure how much decreasing the PVCC voltage from 18V to 12V changes the current draw, but I can check this on the EVM if you like.
To clarify you are running the TAS5731 at 18V and using a boost converter to regulate a 12V supply to 18V?
Do you know what the efficiency of your boost converter is? I believe boost convert efficiency can vary between 70-90%. Your calculation assumes 100% efficiency, but 70% efficiency puts you below 50mA of current at 18V so I think this may be something to rule out. Is it possible for you to measure the current directly into the TAS5731 at 18V?
Also are you using the same conditions used by the datasheet? TA = 25°, DVDD = AVDD = 3.3 V, RL= 8 Ω, BTL AD mode, fS = 48 kHz. Is it possible that you are using the device with a smaller load? Clarifying these test conditions will help us rule out potential causes for the higher current you are observing before looking into the schematic you are using.
At 90% efficiency for the LM3488: 100mA*12V/18V*.9 = 60mA current draw by the TAS5731 so you are right that this is a bit higher than expected. You said that you are running with a 4ohm Woofer & 8ohm Tweeter on each channel. The datasheet current readings that you referenced state that they are for "no load". Having those loads connected could be causing the additional current draw that you are experiencing.
