About power consumption of ADAU1452 for Hibernate mode

Hello Takepiro,

A1. The hibernate bit simply stops the DSP core from running the program. The DVDD current in a hibernate state will not be equivalent to the DVDD current in a reset state. We do not characterize the DVDD current in a hibernate state, and that is why it does not appear in the datasheet's Specifications tables. In order to optimize power savings when the DSP is inactive, it might be best to use Register 0xF890 (SOFT_RESET), or to actually do a hardware reset.

A2. In addition to the POWER_ENABLEn registers, you can use many other registers to lower power consumption. You can, for example, lower the drive strength of I/O pins, disable or mute unused ASRCs, disable the data routing to unused serial ports, disable unused S/PDIF interfaces, set unused serial ports to clock slaves...

Thanks,

Brett

Dear Brett-san,

Thank you for your supports.

My customer has interest in useing hibernate state.

Because it doesn't need re-boot.

Q3:

Do you have a schedule of characterization of the DVDD current in hibernate state?

Q4:

Do you have about value of the DVDD current in hivernate state?

Best regards,

Takehiro Yabune

A3. We are not including DVDD hibernation current measurements in our characterization.

A4. The DVDD current does not change in hibernation mode. However, there is a way to significantly lower power consumption when you want the program to stop executing. Just follow these steps:

Enter hibernate (address 0xF4000 set to 0x0001)

Disable PLL (address 0xF003 set to 0x0000)

Now, the DVDD current will drop to its idle level. For a typical setup, at room temperature, this will be about 10 or 15 mA. To re-enable the DSP execution, follow these steps:

Enable PLL (address 0xF003 set to 0x0001)

Exit hibernate (address 0xF4000 set to 0x0000)

Dear Brett-san,

Thank you very much.

Best regards,

Takepiro