Hi,
My customer raised a complaint about a sudden surge of current consumption on DAC8771 when they trigger open circuit condition.
There are a total of 4x DAC8771. All 4 DAC are using same settings.
They connect the ammeter to the whole system, when in normal operation, DAC Data Register (0x05) with none zero value, no open circuit happen, the current consumption of our whole system is 0.22 to 0.3A.
However, when we purposely trigger open circuit condition, the current consumption for whole system goes up to 0.66A (heat up happen at this moment).
We did a trial to narrow down to DAC8771 current consumption spike as below:
- Whenever the open circuit fault happens, detected by Status Register (0x0B) -> F, we set DAC Data Register (0x05) to 0, the current consumption of the whole system immediately drops back to 0.22 to 0.3A
Please let us know if you notice any inappropriate in our settings below.
The bits I type out are the bits we set, the bits that not type out follow defaults.
1. Reset Config Register (0x02) -> CLRENA = 1
-> REF_EN = 1
2. Select DAC Register (0x03) -> CHA = 1
-> DSDO =
3. Configuration DAC Register (0x04) -> OTEN = 1
-> RANGE = 0110
4. Select Buck-Boost Converter Register (0x06) -> DC = 1
5. Configuration Buck-Boost Register (0x07) -> PNSEL = 01
6. DAC Data Register (0x05) -> depend on user input
The above setting will be used throughout the firmware flow.
May I know if you see anything incorrect in the settings or does a schematic is required to review the case better?
Thanks,
Christina