UC3C ADC and DAC power consumption

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I'm using a UC3C1128C in 5V configuration with an external 3.0V reference. The datasheet says 7ua/Mhz for the ADC and 3ua/Mhz for the DAC. Although it says that includes power from VDDANA I have doubts.

I'm running the CPU and the buses at 7.3728Mhz. The A/D is setup for no S/H with 2 channels being converted using a 460800Hz clock. The 5V current increases by 3.88ma when the A/D is configured and started. A lot higher than the 52ua the datasheet suggests.

For the DAC it's running with 1 output at an update rate of about 25Khz if I remember correctly. The 5V current increases by 2.34ma when it is configured and started. Again, a lot higher than the 22ua the datasheet suggests.

Anyone else measured actual ADC and DAC current consumptions?

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Hi, I bumped in to the same problem. I tried reduce power consumption of the ADC by enabling SLEEP in ADC CFG register. The power consumption seems be reduced, but I do not understand how to use it??? From documentation it seems that by starting conversion the analog part of ADC is powered up as a result of this, but it seems not to be true. On the other hand, if I disable SLEEP before start of conversion and enable after conversion the converted value is OK. Thanks for help Filip.